Tankless water heaters have revolutionized the way we heat water, offering an endless supply of hot water on demand without the bulky storage tank. In this comprehensive guide, we’ll compare the major tankless water heater brandsavailable today – including Rinnai, Navien, Noritz, Takagi, Rheem, Bosch, Stiebel Eltron, EcoSmart, Eccotemp, Camplux, and Marey – across a range of factors like performance, durability, energy efficiency, tech features, installation, size, eco-friendliness, warranty, and customer service. Whether you’re in North America (USA, Canada) or the UK, this article will help you understand the strengths and weaknesses of each brand and find the best fit for your needs.
Introduction to Tankless Water Heaters
Tankless water heaters (also known as on-demand or instantaneous water heaters) heat water without a storage tank. Instead of keeping 40–50 gallons of water hot all day like a traditional tank heater, a tankless unit heats water only when you open a hot tap. This fundamental difference brings several benefits:
• Endless Hot Water: Because water is heated as it flows through the unit, you won’t “run out” of hot water. This is a game-changer for families – no more scheduling showers or waiting for a tank to refill and reheat.
• Energy Efficiency: Tankless systems avoid the standby heat loss that tank heaters have (losing heat from stored water over time). By heating water only when needed, they can be more energy-efficient, leading to lower utility bills. Gas-fired tankless heaters often boast energy factors in the 0.80–0.96 range (up to 96% efficient for the most advanced condensing models), while electric tankless heaters are near 99% efficient at the point of use.
• Space Savings: Without the need for a large tank, these units are compact and wall-mounted, freeing up floor space. They’re ideal for small utility closets, garages, basements, or even outdoors (if rated for exterior installation). This compactness is a big plus for apartments, condos, and smaller homes where space is at a premium.
• Longevity: Tankless water heaters typically last 15–20 years or more, outlasting most tank-type heaters (which last around 8–12 years). The longer lifespan can offset the higher upfront cost over time. Many brands use high-quality components (like stainless steel or copper heat exchangers) to ensure durability.
• Modern Features: Today’s tankless units often come with digital controls, remote thermostats, and even smart connectivity. Some can integrate with Wi-Fi apps for monitoring and adjusting settings from your phone, and a few gas models include recirculation pumps for instant hot water at the tap (more on this later).
Why are tankless heaters so popular today? In short, they align with modern preferences for energy savings, convenience, and smart home integration. Homeowners love the idea of endless hot showers and less wasted energy. In places like the UK and Europe, tankless systems (often in the form of combination boilers) have been common for decades due to space constraints and efficiency demands. North America has been rapidly catching up, with more homeowners replacing old tanks with sleek tankless units each year.
Of course, tankless water heaters also have some considerations to keep in mind. For example, sizing is crucial – a unit must be chosen to meet your household’s peak hot water demand (measured in gallons per minute or GPM). If undersized, you might find the water temperature dropping when multiple taps or showers run simultaneously. Additionally, gas tankless heaters require proper venting and may need a larger gas line, and electric tankless heaters may require an electrical panel upgrade due to their high power draw. These factors make installation a bit more complex on average than a tank heater, so professional installation is often recommended (and sometimes required by the manufacturer to maintain warranty coverage). Despite these challenges, the benefits are often well worth it, which is why tankless units are preferred by many homeowners today.
In the sections below, we’ll dive into the top brands in the tankless water heater market – both gas and electric – and compare them on key aspects like performance, efficiency, durability, and more. We’ll also include a comparison table to summarize the differences, and we’ll offer tips on how to choose the right brand and model for your needs. Let’s get started!
Comparison of Top Tankless Water Heater Brands
When comparing tankless water heater brands, it’s important to note that each has its own niche. Some brands specialize in high-performance gas tankless heaters suited for large homes, while others excel in electric tankless technology for point-of-use or smaller applications. We’ll cover each brand in detail, highlighting their history, what they’re known for, and how they stack up in terms of performance, durability, efficiency, features, installation, size, eco-friendliness, warranty, and reputation.
Rinnai – The Efficiency Expert in Tankless Heating
A wall-mounted Rinnai tankless water heater installed in a home. These compact units save space and provide high-efficiency on-demand hot water.
Overview: Rinnai is a Japanese brand (founded in 1920) that has built a solid reputation for high-efficiency gas tankless water heaters. Rinnai is one of the oldest and most trusted names in the industry, and their products cater to a wide range of household sizes and hot water needs. In North America, Rinnai has become synonymous with quality – it’s a brand often recommended by plumbers for its reliability and performance.
Performance & Flow Rate: Rinnai offers a wide range of models, from smaller units suitable for one-bathroom homes to large units that can supply 5+ GPM of hot water to multiple outlets simultaneously. Their high-end models, like the Rinnai RU/RUR series, can deliver around 9–11 GPM (gallons per minute) under ideal conditions, which is enough to handle running showers, faucets, and appliances at the same time. This makes Rinnai great for larger families or anyone with high hot water demand. Rinnai heaters are also known for excellent temperature stability – they adjust burner output dynamically to keep your shower comfortably hot without noticeable fluctuations.
Energy Efficiency: Rinnai has been at the forefront of improving efficiency. Many Rinnai models are Energy Star certified and use condensing technology to achieve very high efficiency (uniform energy factors up to ~0.95–0.96 on their top models). Condensing Rinnai units have a secondary heat exchanger that captures extra heat from exhaust gases, squeezing more heat into the water and lowering gas usage. Even their non-condensing “Value” series units are quite efficient (around 0.82–0.85 UEF), and all Rinnai units only fire the burner when hot water is needed, avoiding standby losses. In short, fuel efficiency is a strong point for Rinnai, which can translate to energy savings over the heater’s life.
Durability & Build Quality: Rinnai tankless heaters are praised for durable construction with quality components. Built in Japan (or in their international factories with Japanese quality control), these units often last 15–20 years with proper maintenance. Rinnai uses high-grade heat exchangers (usually copper primary heat exchangers, and stainless steel for the condensing secondary exchangers in their higher-end models). They also incorporate safety features to prevent overheating and to shut off if an issue is detected. Many homeowners report trouble-free performance for years. If maintenance is needed (like annual flushing in hard water areas), Rinnai units are generally straightforward for professionals to service. The brand’s focus on durability is backed by a strong warranty: typically around 12 years on the heat exchanger, 5 years on parts, and 1 year labor for residential installations (always check your specific model’s warranty details). This warranty reflects the confidence Rinnai has in its products’ longevity.
Technology & Features: Rinnai doesn’t skimp on modern features. For example, Rinnai’s high-end models offer Circ-Logic™ technology, which can work with a recirculation pump to reduce the “cold water sandwich” effect and deliver hot water to fixtures faster. Some units (like the Rinnai RUR models) even have a built-in recirculation pump and a small buffer tank – a unique hybrid approach that keeps a trickle of hot water ready in the lines, so you get near-instant hot water when you open a tap. This is great for homes where plumbing runs are long and you’d otherwise wait a while for hot water. Rinnai also offers Wi-Fi connectivity on select models (via their Control-R module or newer integrated Wi-Fi in certain series). With the Rinnai app, you can monitor your heater, adjust temperature, activate recirculation remotely, and get maintenance alerts. Not all models have Wi-Fi out of the box, but many are Wi-Fi ready if you add the module. Another nice feature: Rinnai units are designed to be field-convertible between natural gas and propane in many cases, which adds flexibility if your fuel source changes.
Installation & Size: Rinnai tankless heaters are compact wall-mounted units, roughly the size of a small suitcase. A typical unit might be about 2 feet tall and a bit over a foot wide/deep. This compactness makes them easy to fit in utility areas, basements, or even outside (several models are approved for outdoor installation, coming with vent screens and freeze protection down to about -30°F when properly installed). Installation of a gas tankless like Rinnai is more complex than a plug-and-play appliance – you’ll need proper venting (stainless steel vent pipe for non-condensing units, or PVC/CPVC for condensing units which have cooler exhaust), an adequate gas supply line (many Rinnai models need a 3/4” gas line to deliver enough fuel for the high BTU burner), and proper combustion air if installed indoors. Rinnai units are often installed by professional contractors because correct installation is critical for safety and performance. One advantage with Rinnai is that they are widely available – you can buy them through plumbing supply stores, online retailers, and even big-box stores like Home Depot or Lowe’s. This widespread availability means it’s easier to find parts and installers familiar with the brand. However, because they can be bought by anyone, occasionally DIYers attempt installation – Rinnai strongly recommends professional installation, and improper setup can lead to issues or void the warranty. If installed correctly, Rinnai heaters have excellent reliability.
Eco-Friendliness: With high efficiency and low NOx burner technology (meeting strict emission standards in places like California), Rinnai’s gas heaters are relatively eco-friendly for fossil-fuel appliances. By using less gas to heat the same amount of water (especially in condensing models), they produce less greenhouse gas per hot shower compared to older, inefficient heaters. Electric models are not part of Rinnai’s lineup (Rinnai focuses on gas/propane and also now offers some hybrid and heat pump systems, but no pure electric tankless), so if you prefer an electric tankless, Rinnai is not the brand to choose. However, for natural gas or propane users wanting to minimize environmental impact, a high-efficiency Rinnai is a good option. The long lifespan also means fewer units end up in landfills over time.
Customer Service & Brand Reputation: Rinnai’s reputation in the industry is excellent. Customers and professional installers frequently praise Rinnai for its dependable performance. If issues arise, Rinnai has a solid support network. They often work through authorized service providers for any warranty claims or repairs. In North America, Rinnai has a presence in many regions, so getting service or support is usually straightforward. The company’s literature and website provide plenty of info for troubleshooting and maintenance. One thing to note: Because Rinnai is a premium brand with premium performance, the upfront cost of Rinnai units can be higher than some competitors. Also, as mentioned, installing it correctly (venting, gas lines, etc.) might add to the cost if modifications are needed. Nonetheless, owners often feel the investment is worth it for the peace of mind and long-term savings.
Bottom Line: Rinnai is a top choice if you’re looking for high performance, high efficiency, and proven reliability in a gas tankless water heater. It’s ideal for medium to large households that need a robust hot water supply. Just be prepared for a higher initial cost and ensure professional installation. With Rinnai, you can expect a unit that, with proper care, will last many years and deliver excellent service. (For specific model pros and cons, check out our individual Rinnai unit reviews on our site – we’ve reviewed models like the Rinnai V53, RUCS, and others in detail.)
Navien – Cutting-Edge Technology and Condensing Efficiency
Overview: Navien is a South Korean brand (founded in 1978) that has rapidly become a global leader in tankless water heaters, especially known for its advanced condensing technology and innovative features. Navien entered the North American market later than some Japanese competitors but quickly gained traction by offering extremely high efficiency gas tankless units and was an early adopter of built-in recirculation systems. If Rinnai is about tried-and-true reliability, Navien positions itself as a technology and efficiency trendsetter in the tankless arena.
Performance & Flow Rate: Navien’s product line primarily consists of high-capacity condensing gas tankless heaters. Their popular NPE series (Navien Premium Efficiency) includes models like the NPE-240 that can output roughly 10–11 GPM of hot water (at a 35°C/63°F temperature rise), putting them among the highest-output residential tankless units. This means Navien units can handle multiple simultaneous showers in warm climates, and still supply at least 4–5 GPM in colder climates with higher temperature rise needs – plenty for an average household’s use. One hallmark of Navien is the ComfortFlow® system found in their “A” series models: it includes a small built-in buffer tank and recirculation pump. The buffer tank (approximately 0.5 gallons) helps eliminate the cold water sandwich (that sudden burst of cold water you sometimes get in the middle of a hot shower when a tankless hasn’t been firing continuously). It keeps a small reserve of hot water ready to go. The internal recirculation pump can be programmed to periodically circulate hot water through your plumbing (if you have a dedicated return line or even through existing lines with Navien’s recirc valve kit), meaning faster hot water delivery to fixtures at the far end of the house. This is a standout feature in terms of performance convenience – Navien was one of the first to offer this built-in, whereas other brands often required an external pump.
Energy Efficiency: Efficiency is where Navien truly shines. All Navien gas tankless models sold in North America are condensing units, boasting energy factors up to 0.95 or 0.96 UEF. This places Navien at the top tier of efficiency, turning more of the fuel into hot water and less into wasted exhaust heat. The dual stainless steel heat exchangers in their design extract maximum heat, and stainless steel is highly resistant to corrosion (important, because condensed flue gases are acidic). Navien’s focus on condensing technology means you’ll need to accommodate condensate drainage (a plastic tube to drain away the acidic water that forms), but it pays off in lower gas bills and a greener footprint. Navien units are also Low NOx and meet strict emission standards. For those interested in eco-friendliness, Navien’s efficiency means less gas burned for the same hot water output. One small consequence of condensing designs is that the exhaust is relatively cool (because heat is captured) and thus can be vented with PVC in many cases, which simplifies installation. However, Navien’s powerful fan and long vent runs possible might need 2″ or 3″ PVC pipe out of the house. If you’re replacing an old tank heater, the vent will likely need rework (most tank heaters use smaller metal vents). Navien does supply an adapter for 2-inch PVC venting and options for concentric vent kits (one pipe inside another for intake and exhaust).
Durability & Build Quality: Navien units are well-built, but as a technology-forward brand, they have a lot of components packed inside (pumps, fans, electronic boards, etc.). The heat exchangers being stainless steel is a major plus for longevity, as they resist scale and rust. Many users report Navien units running reliably for years, especially if installed correctly and maintained (like flushing the heat exchanger annually in hard water areas). Some plumbers note that Navien’s design is a bit more complex than simpler tankless units, which can mean there are more things that could require service (for example, the built-in pump or valves). However, Navien has improved their designs over the years to enhance reliability. The brand typically offers warranties around 15 years on the heat exchanger, ~5 years on parts, and 1 year labor for residential use (similar to other top brands). Navien’s commitment to quality is solid, but because they haven’t been around as long in the U.S. as some others, you might find slightly mixed reviews on longevity – some users have had zero issues, while a few others experienced component failures (like flow sensors or control boards) after a number of years. It’s worth noting that Navien often updates its models to address any recurring issues. Ensuring you have a qualified Navien installer can also impact how well the unit performs over time.
Technology & Features: We’ve already mentioned some of Navien’s marquee features like the built-in recirculation pump and buffer tank (on their “A” models). Even Navien’s “S” series (without the buffer tank) still often have the pump and can recirculate water from an external line. Navien also offers the NaviLink® Wi-Fi control system, an optional add-on that allows you to connect your heater to your smartphone. Through the app, you can remotely turn the unit on or off, set recirculation timers, adjust temperature, and receive diagnostic notifications. This is great for integrating into a smart home system. Navien’s interface on the unit is user-friendly too – a digital display allows precise temperature setting (in increments of 1°F or 1°C) and provides error codes for troubleshooting. Another innovative offering from Navien is their combi-boiler line (NCB series), which can provide both domestic hot water and home heating (for radiators or in-floor heating). While that’s a separate product category, it shows Navien’s breadth in home comfort solutions. For our focus on tankless water only, one more Navien feature to mention is their use of dual heat exchangers(two stainless steel exchangers) which not only improve efficiency but also share the workload, potentially extending the life since each exchanger handles less thermal stress compared to a single one doing all the work.
Installation & Size: Navien units are relatively compact, but due to the buffer tank and pump, their casings are a bit larger than some competitors. They typically measure around 24” high, 17” wide, and 13” deep – still small compared to a tank water heater, but among the larger in the tankless category. Installation of a Navien must account for venting (usually PVC) and condensate drainage (a simple plastic tube to a drain or neutralizer). If you’re installing a Navien in a retrofit, you might need to purchase Navien’s accessory kits, such as the external recirculation valve (if you don’t have a dedicated return line but want to use the internal pump, Navien can recirculate via the cold water line with a special valve under the sink farthest away). Navien requires a professional installation for warranty purposes in many jurisdictions, and given the complexity, it’s wise to use a plumber or HVAC technician who has experience with Navien. Some installers have noted that Navien units weigh a bit more (due to that buffer tank) and have slightly different venting setups, so not every plumber is equally comfortable with them. However, Navien does provide training to contractors and has tech support to assist. Once installed, users often comment that Navien provides hot water very quickly, especially if the recirculation is set up – the convenience is noticeable. If installing outdoors, Navien has outdoor models or kits too (with built-in heaters to prevent freezing), but outdoor installation is more common in milder climates.
Eco-Friendliness: As a condensing unit with top-tier efficiency, Navien is about as eco-friendly as gas-fired water heating gets. Using less fuel for the same output means reduced carbon emissions per gallon of hot water. Additionally, Navien’s low-emission burners cut down on nitrogen oxide (NOx) which contributes to smog. If you’re concerned about greenhouse gases, any gas appliance will have a carbon footprint, but at least Navien minimizes it. For those considering electric tankless for eco reasons (to possibly use renewable electricity), Navien doesn’t have electric models – they are focused on natural gas and propane solutions. One could argue that an electric tankless can be “greener” if powered by solar or wind, but in many regions, the source of electricity might be fossil fuels as well. Navien’s approach is to make gas as efficient as possible. The company also contributes to eco-friendly building by meeting requirements for green building programs with their high EF ratings.
Customer Service & Brand Reputation: Navien’s reputation is generally positive, especially on the technology and efficiency front. Many homeowners love the features and notice the difference in comfort (hot water delivery speed, etc.) compared to other heaters. However, Navien being a newer entrant in some markets means customer service experiencescan vary. Some customers have reported excellent support and warranty service, while others have faced delays or difficulties in getting service parts. One thing to note is that Navien units are often sold through professional channels(plumbing distributors) rather than off-the-shelf at retail. This means Navien expects you to go through an installer, and that installer often handles any issues with Navien on your behalf. As long as you have a responsive installer, your experience should be smooth. Navien’s documentation is thorough, and they have a robust set of diagnostic codes to help pinpoint issues if they arise. On forums and Reddit, you’ll find debates between Navien vs Rinnai vs Noritz – where Navien fans tout the features and efficiency, while others might prefer the simplicity of some older Rinnai/Noritz units. Overall, Navien is considered a top-tier brand, and the choice often comes down to whether you value the extra features and can ensure a good installation. If you do go Navien, the reward is a cutting-edge system that offers comfort and efficiency at the same time.
Bottom Line: Navien is an excellent choice if you want the latest and greatest in tankless tech – especially the built-in recirculation and high efficiency. It’s perfect for tech-savvy homeowners or those with large households who don’t mind paying a bit more for premium features. Just remember that professional installation is key to unlocking Navien’s potential. Our site has individual reviews of Navien models (like the NPE series) where we discuss specific pros, cons, and user experiences, so be sure to check those out for more details on performance and maintenance.
Noritz – Innovation and Customization from a Pioneer
Overview: Noritz is another Japanese giant in the tankless water heater industry, with a history dating back to 1951 and a pedigree of introducing the first modern tankless water heater to Japan in 1981. Noritz might not be as instantly recognized by consumers as Rinnai or Rheem, but among professionals, Noritz is highly respected for its quality and innovative approach. Noritz offers a wide range of models and has been a pioneer in certain technologies and installation-friendly designs. If we were to sum up Noritz, it would be quality meets innovation, with a focus on giving customers options to suit different needs.
Performance & Product Range: One of Noritz’s strengths is its extensive product line, often regarded as one of the most customizable. They make everything from small residential units to heavy-duty commercial tankless systems. In North America, Noritz offers high-output condensing gas models (like the Noritz NRC series) capable of around 9–11 GPM, as well as non-condensing models in the 6–9 GPM range. For example, the Noritz NRC98 or NRCP series can support multiple showers concurrently, similar to other top brands. Noritz also produces a unique line called the EZ Series which is specifically designed to make replacing old tank heaters easier – these have top-mounted connections that align more closely with where tank heater connections are, helping plumbers swap in a tankless with less re-piping. They even allow re-using the existing vent in some retrofit scenarios by using 2” flex venting through the old vent pipe (for certain models), which can reduce installation complexity. This shows Noritz’s innovative bent toward solving real-world installation headaches. In terms of performance consistency, Noritz units are known for delivering steady temperatures. Like others, they modulate flame size to match flow demand. Some Noritz models are better for colder climates (they advertise efficient performance even when incoming water is very cold, if properly sized). If you have a really large demand, Noritz allows connecting multiple units in cascade for commercial or large home use – not unique to Noritz, but they have robust kits for linking units.
Energy Efficiency: Noritz offers both condensing and non-condensing units. Their condensing models (with “C” in the model name, e.g., NRC..) reach high efficiency levels around 0.90–0.95 UEF, competitive with Navien and Rinnai’s best. A standout efficiency-oriented feature from Noritz is their Hydrogen Eco Burner technology – some models can utilize a mix of hydrogen and natural gas (anticipating a future where hydrogen blending in gas lines might be more common to reduce carbon emissions). This forward-thinking approach underlines Noritz’s commitment to eco-friendly innovation. Additionally, Noritz has models with dual heat exchangers (stainless steel secondary exchanger) for condensing operation. They also focus on low NOx emissions. An interesting aspect is Noritz’s emphasis on scale detection and prevention. Some units have tech that can monitor for scale buildup (hard water mineral deposits) and alert the user, which indirectly preserves efficiency by prompting maintenance before a heavy scale layer insulates the heat exchanger. Overall, Noritz is very much on par with other top brands in efficiency, and you’ll find Energy Star ratings on many of their units.
Durability & Quality: Noritz stands out for robust build. They use commercial-grade copper for primary heat exchangers and stainless steel for secondary (in condensing models). Their components are built to last, which is why Noritz units often have a reputation for lasting 20+ years. Many professional installers note that Noritz heaters are very well engineered internally – parts fit together tightly, and there’s attention to details that matter in the long run (like better resistance to corrosion or heat stress). Noritz’s confidence shows in their warranties: often 12 to 15 years on heat exchangers (depending on model and usage), around 5 years on parts, and 1 year labor. To maximize lifespan, Noritz, like others, should be maintained (flush yearly or use a scale inhibitor if you have hard water). But thanks to using high-quality materials, Noritz units can handle some tough conditions. For example, many Noritz models come with built-in freeze protection heaters, allowing them to be installed in cold areas (or even outdoors in cold climates, as long as they have power to run the anti-freeze circuitry). This shows a durability consideration at the design stage. If anything, the only caution on durability is that, similar to Rinnai, Noritz usually sells through professional channels, so a DIY poorly-installed Noritz might face issues (but that’s more of an installation problem than a product quality issue). Noritz’s track record worldwide is excellent; they might be “quietly” reliable, not always as high-profile in marketing, but their gear is built to last.
Features & Technology: Noritz may not always shout about smart features as much as some others, but they do offer Wi-Fi capability through an adapter (the Noritz Wi-Fi adapter and app allow remote control and monitoring). They also have some models with built-in recirculation pumps (e.g., the NRCP series) to provide similar benefits to Navien’s comfort flow – recirculation for instant hot water. If you don’t get a model with a pump, Noritz units are often compatible with external pumps and they have control logic to work with them. A unique offering from Noritz is their combination tankless + storage hybrid unit (like the Noritz EZ Series “Storage” hybrid) which pairs a small tank with a tankless in one unit – giving both rapid response and sustained output. This is a niche product, but again highlights customization; it can be useful if you have a situation where a single tankless struggles with peak demand, the little tank supplements it for short bursts. Noritz also has an impressive safety feature set: automatic shutdown in case of overheating, flame failure detection, and even sensors for vent blockage or gas leaks in some models. These protections give peace of mind, especially for indoor installations. From an installation tech perspective, Noritz is known for offering a variety of venting solutions – for example, certain Noritz models can vent with a single exhaust pipe and take combustion air from the room, or use twin pipe, or concentric, giving flexibility based on your needs. They even allow long vent runs (some can vent 65+ feet with powerful fans), which is helpful in retrofitting. While Noritz might not have the flashy marketing of “app-driven recirc schedules” as Navien does, in practice you can achieve similar results with Noritz’s tools. One area where Noritz has been innovative is in eco-friendly burner design (as mentioned, prepping for hydrogen mix) and in making their units installer-friendly (the top-mounted connections on EZ Series, for instance, or the ability to common vent two units’ exhaust into one pipe for certain commercial installs).
Installation & Accessibility: Noritz tankless heaters are widely used by professional installers. They historically sold through plumbing wholesalers, meaning an installer would recommend and provide the unit. In recent years, Noritz has also made a push into the DIY/retail space with some models available online. However, a lot of Noritz’s special features (like the EZ Series top connections or bundled valve kits) are aimed at making life easier for a licensed installer doing a replacement job. If you go with Noritz, finding an installer who is familiar with them is a good idea – many plumbers love Noritz once they’ve worked with them, because they encounter few call-backs later. Size-wise, Noritz units are typical of gas tankless: wall-hung boxes roughly 2 feet tall, with variations in width/depth. The condensing units might be slightly larger due to dual heat exchangers. Noritz offers both indoor and outdoor models (outdoor models have waterproof casing and built-in vents on the front). One important note: Noritz, like others, does not manufacture electric tankless heaters. They are focused on gas/propane. So for installation, you will need the proper gas line capacity (often 3/4” line and up to 150k–200k+ BTU for bigger models) and appropriate venting. Noritz’s venting options include their proprietary concentric vent system or standard PVC for condensing units. They often require a category III stainless steel vent for non-condensing units (which can add cost if not already in place). For water and gas hookups, Noritz units generally come with isolation valve kits (or your installer will add them) to facilitate flushing and servicing. Many Noritz units also have an easily accessible inlet water filter screen that you or a technician can clean periodically to ensure debris doesn’t clog the heat exchanger – a thoughtful design detail.
Eco-Friendliness: Noritz emphasizes eco-friendly operation. Many models have very low NOx emissions (meeting California’s stringent requirements). The high efficiency of their condensing line means less gas burned. If you’re environmentally conscious, you’ll also appreciate that Noritz has been working on compatibility with emerging fuel mixtures (like up to 20% hydrogen blend), which positions their products for a greener future as gas utilities start to experiment with renewable gas blends. This isn’t a factor that will affect your day-to-day use, but it shows Noritz is thinking ahead to reduce carbon footprints. Additionally, because Noritz units last a long time, there’s less frequent manufacturing and waste compared to cheaper units that might fail sooner – an often overlooked aspect of sustainability is product longevity.
Customer Service & Support: Noritz generally operates through trained contractors, so your first line of support is usually the installer. That said, Noritz USA has tech support lines that both contractors and sometimes end-users can call for help. The company provides detailed installation manuals and has some online resources for troubleshooting. In terms of customer satisfaction, Noritz users often become very loyal to the brand; complaints are relatively few. One reason you might not see Noritz advertised as much is that they focus on the pro market, but those in the know often stick with Noritz for multiple home projects after a good experience. If your region has fewer Noritz dealers, that could affect getting service in rare cases, but generally any skilled tankless technician can service a Noritz since the principles are similar across brands. Brand reputation for Noritz is strong in Asia and growing in North America. They might not have as much retail presence, but they are counted among the top-tier brands alongside Rinnai and Navien. Think of Noritz as a bit of an unsung hero: not as flashy in advertising, but rock-solid in performance.
Bottom Line: Noritz is a great choice if you value quality and innovation in equal measure. They offer some of the most installer-friendly and customizable solutions, which can benefit you in getting a tankless that fits your home just right. Noritz is particularly appealing for environmentally conscious buyers and those planning long-term, since their units are built to last and adapt to future needs. Be sure to use a knowledgeable installer to get the full benefit of Noritz’s features. If you’re interested in specific Noritz models, check our site’s individual reviews – we’ve covered models like the Noritz EZ Series and NRCP units, providing pros/cons and insights from real-world use.
Takagi – Safe, User-Friendly, and Value-Oriented
Overview: Takagi is a Japanese manufacturer that has been making tankless water heaters since 1952. In North America, Takagi might not be as immediately famous as Rinnai or Navien, but they have a strong following, especially among those looking for affordable yet reliable gas tankless options. Takagi’s focus has traditionally been on simplicity, safety, and solid performance without too many frills. They often come in at a slightly lower price point than the big names, making them a popular choice for smaller families or budget-conscious buyers who still want a quality unit. (Takagi has also partnered with A. O. Smith in the U.S., meaning some A. O. Smith or State branded tankless units are actually Takagi under the hood.)
Performance: Takagi offers a range of gas tankless heaters suitable for different home sizes. Their lineup includes mid-sized models (around 6–8 GPM output) which are great for small to medium households, as well as larger models (9–10 GPM) for bigger homes. They typically label their units by max flow or input BTU (for example, the Takagi T-H3 series are high BTU, high flow units suitable for whole-home use, whereas the T-KJr2 is a “Junior” model for lower demand scenarios). In real-world terms, a Takagi T-H3-DV-N (a high-end indoor condensing model) can handle two to three showers running simultaneously in warm climates, or one to two in colder climates – comparable to other 180,000+ BTU units. Takagi units are known for quick ignition and response, so you don’t wait long for hot water to start flowing. They modulate well at lower flow rates too, with many models able to fire even at flow rates as low as 0.4 GPM (important for low-flow faucets or when just trickling hot water). One thing to note is Takagi historically didn’t integrate recirculation pumps or buffer tanks; their philosophy has been to keep things straightforward. If recirculation is needed, an external pump and controller can be added, but Takagi doesn’t include it built-in. So in terms of performance, Takagi excels at fundamental tankless performance – continuous hot water – but generally without some of the extra convenience features some competitors offer.
Energy Efficiency: Takagi produces both condensing and non-condensing models. Their condensing models (often denoted by “T-H3” or “T-H2” etc.) reach efficiency levels around 0.93–0.95 UEF, putting them in the high-efficiency category. Non-condensing models are typically around 0.80–0.82 EF. Takagi perhaps isn’t as flashy about efficiency as Navien, but in practice their units are right up there with other top brands. One area Takagi stands out is cold-weather performance – some Takagi units are known to handle cold incoming water quite efficiently (provided they are sized correctly, of course). They incorporate features like air-fuel ratio sensors and exhaust sensors to maintain optimal combustion, which indirectly optimizes efficiency and emissions. Speaking of emissions, Takagi was one of the first to have fully Low-NOx compliant units across their range, meeting environmental regulations. This is a plus if you live in areas like California or Texas where Low-NOx is required. As for electricity usage, Takagi units, like all gas tankless, do need electricity for the computer board and ignition (and for the fan, plus condensate pump in some cases if installed in a basement). They sip very little power for these functions (comparable to a light bulb). There are no Wi-Fi or fancy electronics drawing power when idle – a nod to simplicity and efficiency.
Safety Features: Takagi puts a big emphasis on safety, which is worth highlighting. They include robust safety systems: overheat cut-off fuses (to shut the unit down if it starts to overheat), flame failure detection (to stop gas flow if the flame goes out), surge protection on the electronic board, and troubleshooting error code displays. The overheat cutoff is particularly notable – Takagi has a reputation for not compromising on safety controls, which has made their units very safe for indoor installations. Additionally, Takagi units have freeze protection heaters on their heat exchangers so the internal pipes don’t freeze in cold weather (down to around -30°C/-22°F typically, if powered). This allows outdoor installation in many climates (though extremely cold climates still favor indoor installs or additional enclosure heating).
Durability & Build: In terms of durability, Takagi units use high-quality copper for heat exchangers (and stainless for condensing secondary exchangers). They might not have quite the same heavy-duty feel as Noritz or Rinnai to some installers, but they are by no means flimsy. Many Takagi owners report their units running strong for well over a decade. The partnership with A. O. Smith has also made parts availability decent (A. O. Smith service dealers often can service Takagi too). The Takagi warranty for residential use is competitive: often around 10–15 years on heat exchanger (10 years is common for some models, some go up to 15 for certain condensing models), ~5 years parts, 1 year labor. Slightly shorter exchanger warranty than Rinnai/Navien in some cases, but still quite robust. This may reflect their confidence in mid-range usage – Takagi sometimes positions their units as “best for smaller families” which implies not running at max fire 24/7, thus easily lasting beyond a decade. That said, Takagi units can absolutely handle continuous heavy use; they’re also used in commercial settings (with shorter warranty for commercial). The maintenance needs are standard – flush annually if hard water, etc. Some Takagi models have convenient service ports and accessible filters. The brand’s association with A. O. Smith means many plumbing companies have experience with them, which indirectly helps with maintaining durability since a knowledgeable tech can keep it in top shape. One possible drawback: Takagi does not make electric tankless heaters (similar to Rinnai/Noritz, they are gas-only specialists). So durability discussion is purely about gas units.
Features & Smart Tech: If there’s one area Takagi is a bit behind the curve, it’s smart tech integration. They do not offer built-in Wi-Fi or smartphone apps for their heaters. Nor do they integrate fancy digital displays on the front (most Takagi units use a simple set of LED status lights or a basic remote thermostat that shows temperature and codes). For many people, this is not an issue – water heaters are often “set and forget” devices. The upside is less to go wrong electronically. The downside is if you want to adjust settings or see usage history from your phone, you won’t have that with Takagi. However, Takagi’s simplicity contributes to their strong user-friendliness. Setting the temperature is typically done via a dip switch or via an optional wired digital remote. Once set, the unit reliably holds that temp. There are no complicated menus to navigate. Some Takagi models allow setting an output temperature as high as 185°F for commercial or sanitation purposes (locked out for residential by default to prevent scalding). This shows they have the power if needed, but of course residential users would stick to ~120°F (49°C) for safety. Takagi units also lack internal recirculation pumps as mentioned; if you need a recirc system, you can pair the Takagi with an external pump and maybe a thermal bypass valve under a sink (to recirculate through cold line) – it’s an extra component to manage, whereas Navien would have it integrated. Depending on your viewpoint, this either simplifies the heater (fewer internal parts to maintain) or denies you a convenience feature.
Installation: Takagi tankless heaters are typically installed by pros, but they are also found in many DIY projects due to their relative affordability and the wide distribution via A. O. Smith channels. They have indoor direct-vent models and outdoor models. Indoor models need stainless steel venting (Category III) for non-condensing or PVC for condensing, similar to others. Outdoor models have their own vent cap and just mount outside, needing no additional vent pipes (just a small condensate drain line if condensing). Physically, Takagi units are compact and wall-mounted like others – around 20-24 inches tall, 14-18 inches wide, 10-12 inches deep, depending on model. They are easily comparable in size to Rinnai or Noritz units of similar capacity. Gas line requirements are the same: ensure sufficient gas supply (they often require ~150,000 to 199,000 BTU capacity, so a 3/4” line). One area where Takagi might cost a bit less on install is that some of their mid-range units have slightly lower BTU ratings, meaning if you’re replacing a 40k BTU tank, a Takagi that’s 140k BTU might be easier on the gas supply than a 199k BTU beast from another brand – possibly avoiding a gas meter upgrade if your demand isn’t huge. This is scenario-specific, of course. Many Takagi models come with the basic accessories (like mounting hardware, power cord) but you’ll need to get isolation valves and vent kits separately. Their manuals are straightforward, and because they align with A. O. Smith models, a lot of plumbers already have familiarity (A. O. Smith Takagi models are essentially the same with different branding).
Eco-Friendliness: Takagi’s eco credentials are solid from an emissions and efficiency standpoint. All current models are Low-NOx. Their condensing units maximize energy usage. One could argue that by not including a constantly running recirculation pump, Takagi avoids unnecessary gas usage – because recirculation, while convenient, does use extra fuel to keep water warm in the lines. With Takagi, you heat on demand and that’s it, which is an efficient approach if you’re willing to wait a few seconds at the tap. Another point: Takagi’s lack of electric models means if you’re looking to go electric for carbon-free (assuming renewable electricity) in the future, Takagi wouldn’t have an offering. But as a gas unit, it’s as eco-friendly as most other top gas units. The safety features and reliability also mean it’s eco-friendly in the sense of preventing fuel waste or accidents.
Customer Service & Support: Takagi is often sold and serviced by A. O. Smith service networks in North America. This can be an advantage because A. O. Smith is a well-known water heater brand with many service centers. There is also Takagi-specific support. Generally, customers find Takagi units don’t require a lot of attention once running, which is the best scenario – “it just works.” If you do need help, you’d typically call the installer or the manufacturer’s hotline. One thing to be aware of: because of the partnership, some plumbers might not even realize a certain model is Takagi-made. For example, if you have an A. O. Smith ATI-540H unit, that’s actually a Takagi T-H3. So, ensure whoever services it knows the cross-reference or can get the right parts. Fortunately, those parts are not hard to get. Brand reputation for Takagi: they are considered a solid mid-to-high-tier brand. Maybe not as premium as Rinnai/Navien in features, but very reliable. Their value proposition (quality vs cost) is often praised. Many homeowners who choose Takagi are those who did their research and realized it offers what they need without extra bells and whistles – and they are often very satisfied. Takagi might not have the sheer brand recognition in the consumer market, but in trade circles, it’s well-regarded.
Bottom Line: Takagi is an ideal choice for those who want safe, reliable hot water without paying extra for features they don’t need. It’s best for small to medium families, or anyone on a budget, but it can scale up to larger demands with the right model. If you’re okay controlling your heater the “old-fashioned” way (i.e., via a thermostat on the unit) and waiting a bit for hot water instead of having built-in recirculation, a Takagi will serve you very well. It offers peace of mind with strong safety measures and a user-friendly experience. Our website includes reviews of specific Takagi models (and their A. O. Smith equivalents) where we outline performance and any pros/cons observed in everyday use – be sure to check those if you’re leaning toward this brand.
Rheem – Reliability Meets Affordability
Overview: Rheem is a household name in North America when it comes to water heaters. Founded in 1925 in the US, Rheem has become one of the largest manufacturers of water heating products in the United States. They are known for everything from big storage tank heaters to innovative hybrid heat pump heaters – and of course, tankless water heaters. Rheem’s tankless lineup covers both gas and electric models, making it a versatile brand for any preference. The key appeal of Rheem is that it offers a balance of performance and value: their products tend to be more affordable than some premium imports, and they are widely available through retail channels like Home Depot and through plumbing wholesalers. This accessibility and a strong support network make Rheem a popular choice.
Performance (Gas Tankless): Rheem’s gas tankless models (often sold under the Rheem or Ruud brand, since Ruud is a sister brand) come in various sizes. For whole-home gas tankless, Rheem offers high-capacity units that can deliver around 8–9 GPM for typical rise (with model numbers often indicating max GPM, like Rheem 9.5 GPM, etc.). Some of their newest high-efficiency models can reach up to 11 GPM in ideal conditions, putting them on par with Rinnai or Navien in terms of flow for their top units. Rheem gas units heat water effectively and have intelligent electronic controls to maintain stable temperatures. Many Rheem models include a water-saving setting that can reduce flow a bit if the outgoing water is not yet up to temp, helping avoid that cold water burst. They also have models with built-in recirculation pumps (e.g., Rheem “Prestige” series) similar to Navien’s approach, which can drastically cut wait times for hot water at fixtures when enabled. This is an advanced feature not always expected from a “value” brand, so Rheem has stepped up in that regard. It’s worth noting that Rheem’s gas units historically were often rebranded Paloma or other Japanese units, but in recent years Rheem has designed more of their line in-house or in partnership with overseas manufacturers. The result is performance that aligns well with what consumers expect: plenty of hot water for typical usage. For example, the Rheem RTGH-95DVL (indoor condensing unit) can handle running a couple of showers and a sink at the same time in many climates. One thing some users mention: Rheem units may have a slightly higher minimum activation flow (sometimes around 0.5 GPM), meaning if you just crack a faucet, it might not trigger the heater as easily as, say, a Noritz which fires at 0.4 GPM. In practical terms, this is minor and usually not noticeable except maybe with very low-flow fixtures.
Performance (Electric Tankless): Rheem is also a major maker of electric tankless water heaters, including point-of-use models and whole-home models (like the Rheem RTEX-24, RTEX-36, etc., which correspond to kW ratings). Rheem’s electric units are known for being easy to find and relatively affordable. They offer digital temperature controls and use self-modulating technology (adjusting power draw based on flow). Electric tankless heaters from Rheem are typically best for small apartments, point-of-use (like a single bathroom or sink), or warmer regions if whole-home, because like all electric tankless, their GPM output is limited by the power (kW) available. For instance, a Rheem 27 kW electric tankless might handle 2 showers in Florida, but only 1 in a colder state where incoming water is frigid. Rheem gives clear sizing guides to help choose the right electric model. The big advantage of Rheem electric units is simplicity and compact size – they often are as small as a shoebox and can fit under a sink or in a closet. They have replaceable heating elements (Rheem, being a tank heater expert, built them a bit like tank elements in a way), which can be serviced. For someone who can’t install gas or doesn’t have the fuel, Rheem provides a reliable electric alternative.
Energy Efficiency: Rheem’s condensing gas tankless models have efficiencies around 0.92–0.94 UEF, competitive with others. Their non-condensing gas units are around 0.82–0.85 EF. They emphasize their EcoNet® smart monitoring system on higher-end models which helps ensure efficient operation by letting users monitor energy usage. (EcoNet is Rheem’s smart home platform – more on that in features). Electric Rheem units are nearly 99% efficient at converting electrical energy to heat (which is true of all electric resistance heaters). One thing to consider is the overall energy cost: in many places, natural gas is cheaper per BTU than electricity, so Rheem appropriately offers both options to cater to whichever is more efficient/cost-effective for the homeowner. Rheem’s focus on efficiency is also seen in features like self-diagnostics that can alert if something is wrong (ensuring the unit isn’t wasting energy due to a fault) and their high-efficiency burners and condensing heat exchangers. Most Rheem condensing units are Energy Star rated. So whether you go gas or electric, Rheem has efficient choices. Rheem also makes hybrid heaters (tank with heat pump) but that’s outside this article’s scope.
Durability & Warranty: Rheem positions itself as a high-value brand, which means durability is good, though perhaps in absolute terms the expensive Japanese brands might use slightly higher-grade components. That said, Rheem’s high-end Prestige line gas tankless heaters are very robust – stainless steel condensing exchangers, etc. Rheem offers a somewhat shorter warranty on parts/labor than some premium brands: typically 12 years on heat exchanger, 5 years on parts, 1 year labor for residential gas units (and sometimes 5 years on heat exchanger for electric models, with 1 year parts). Notably, Rheem often only offers 1 year labor warranty, whereas some other brands might cover labor for longer (though many also do 1 year). This is a minor point unless something fails early. In terms of real-world longevity: Rheem tankless units, if maintained, should easily last over a decade. Many users have them past 10-15 years. If comparing, some might say Rinnai/Noritz can reach 20 years, but Rheem likely can too under good conditions. One area to maintain is to flush gas units and check burner components – Rheem’s network of service technicians is a plus here; since Rheem is common, getting service or parts is generally easier. The availability of parts is a strong suit for Rheem; you can often order parts online or find them locally because Rheem has distribution everywhere. This can aid in keeping a unit running for a long time, since you won’t wait weeks for an obscure part. Also, Rheem’s electric units have readily swappable parts (heating elements, flow sensors, etc.), which makes fixing them potentially simpler than some smaller brand electric units where you might just replace the whole thing if it fails.
Features (Smart Tech): Rheem has embraced smart home integration through its EcoNet® platform. Certain Rheem tankless models (especially in the Performance Platinum/Prestige line) come EcoNet enabled or can be connected with an add-on Wi-Fi module. With the EcoNet app, you can remotely monitor your water heater, get alerts (like leak detection or error codes), adjust temperature, and in some cases, integrate with other Rheem devices (like their HVAC or pool heaters, etc., if you have them). While not as elaborate as some specialized systems, it’s definitely a nice inclusion for a brand that’s often seen as “value” – you don’t have to miss out on connectivity. Additionally, Rheem’s recirculation-capable models allow setting recirculation schedules either via the control panel or app, so you can tailor when you want instant hot water (for example, schedule the pump to run during morning and evening peak times). Another neat feature: Rheem’s gas units have self-diagnostic displays that show maintenance codes. Some models feature an LED or digital display on the front to show temperature and status, making it easy to know what’s happening (no need to decode blinking lights like on older units). In their electric line, Rheem units have digital thermostats on the front where you can dial in the temperature precisely and see it on an LCD screen.
Installation & Accessibility: Rheem’s widespread availability is a big plus. You can find Rheem units at Home Depot (often under the Performance or Performance Platinum series), which makes them a go-to for many DIY-minded homeowners or local contractors. Rheem gas tankless heaters usually come with some installation accessories, but you’ll still need to ensure proper venting (Category III stainless or PVC depending on model). Rheem offers 3” PVC venting on its condensing models which can simplify retrofits. Rheem also sells valve kits, vent kits, and even concentric vent options to streamline installation. Because Rheem tankless units are common, many plumbers are familiar with installing them – this can sometimes translate to slightly lower install costs because the contractor might have confidence from having done many. One note: because they are easily available, some homeowners attempt DIY installs. While an experienced DIYer with gas skills can do it, we always caution that gas, venting, and high-power electric work are best left to pros for safety and to comply with code (and to ensure warranty validity). In terms of size, Rheem units are similar to others: wall-hung, about 2 feet tall and a foot or so wide. They aim to make replacement easy by providing brackets and clear manuals. Another plus for accessibility: Rheem’s customer support is known to be helpful, and because they have call centers in the US, you often can get someone on the line relatively quickly if you have questions during installation or troubleshooting.
Eco-Friendliness: Rheem’s approach to eco-friendliness is offering many options that can improve a home’s energy profile. Their high-efficiency gas units reduce fuel usage. Their electric units allow people without gas to go tankless (though electric tankless can draw a lot of power from the grid; still, no combustion emissions on-site). Additionally, Rheem has been pushing sustainability initiatives – for instance, they have goals to reduce greenhouse gas footprints of their products and have introduced recycled materials in packaging, etc. For a consumer, choosing a high-efficiency Rheem tankless contributes to energy conservation. If you pair an electric Rheem tankless with renewable electricity (solar panels, for example), you could have a very eco-friendly hot water supply. On the gas side, Rheem units are all low NOx now. Also, by making tankless more affordable and mainstream, Rheem helps more households move away from inefficient tank heaters, which broadly is good for reducing wasted energy (since tankless can save 10-20% or more on energy compared to a standard tank).
Customer Service & Brand Reputation: Rheem has a long-standing reputation. Many people have used Rheem products (like a tank water heater) and thus trust the brand. In the tankless segment, Rheem might not be the absolute top performer in every category, but it has the trust factor and an extensive service network. Reviews from users often highlight that Rheem tankless heaters “just work as expected” and that installation was straightforward. There are sometimes mixed reviews, often tied to installation quality – e.g., someone who had it installed improperly might blame the unit. But overall, Rheem’s customer satisfaction is high because of their focus on making the user experience good (e.g., including that digital display and offering Wi-Fi – things that reduce mystery and frustration). One slight downside noted by some is that Rheem being a big company, warranty service can require some persistence; you might have to go through their process which sometimes involves approved service technicians coming out. However, because they are everywhere, it’s usually resolved. Rheem’s reputation among contractors is generally positive, though some high-end installers might favor Japanese brands for ultra-high-end projects. Still, Rheem is often the benchmark for value – others are compared against it.
Bottom Line: Rheem is a top contender if you want a trustworthy, feature-packed tankless heater without breaking the bank. It’s perfect for homeowners who appreciate a mix of innovation (like smart features) and practicality (ease of finding and servicing). Rheem offers both gas and electric models, so it’s a one-stop brand whether you live in a big house with natural gas or a small apartment with only electric service. While it may not have a niche “luxury” cachet, Rheem often exceeds expectations given its price point. We have in-depth reviews of several Rheem tankless models (gas and electric) on our site, where we list pros and cons observed (like the pros of EcoNet connectivity and cons like slightly lower flow in cold climates for electric units). Check those out if you’re considering Rheem, as they’ll help you pick the right model and understand installation considerations more deeply.
Bosch – Precision Engineering and Reliable Performance
Overview: Bosch is a German brand with a storied history in engineering and technology (over 130 years in business). In the realm of water heating, Bosch Thermotechnology has been a key player, especially in Europe. Bosch tankless water heaters (formerly marketed under sub-brands like Bosch AquaStar, and the Bosch Greentherm series) are known for quality construction and efficient operation. Bosch offers both gas tankless models and some electric tanklessoptions, with a focus on delivering consistent performance through intelligent engineering. While Bosch isn’t as dominant in the North American tankless market as some Japanese or American brands, it’s a well-respected name globally and has a niche following in NA for those who trust European brands.
Performance: Bosch’s gas tankless models, such as the Greentherm 9000 series, are high-performing condensing units. For example, the Bosch Greentherm 9900i SE model can deliver around 9–10 GPM at a 35°F rise, placing it among the higher capacity units suitable for medium to large homes. Bosch designs their burners and heat exchangers to provide fast response and minimal temperature fluctuation. One thing Bosch emphasizes is their intelligent electronic flow control: their units monitor the outlet temperature and adjust gas and water flow precisely to maintain a stable output, even if inlet conditions change. This means if someone opens a second tap, the Bosch unit works to keep both outputs at consistent temperature as much as possible. Bosch units often have a slightly wider modulation range, allowing them to handle low flow rates and also ramp up for high flow – giving flexibility. In everyday use, a Bosch gas tankless will give you endless hot water just like others; what Bosch adds is a touch of refinement – some users note that their Bosch heater is very quiet and they hardly notice it running except for the hot water being there. Bosch also has a history with pilot-less hydro-powered ignition on older models (using water flow to generate a spark, thus not needing a battery or external power). Most modern ones use electric ignition, but that legacy shows Bosch’s innovative approach to off-grid use. In their electric tankless lineup, Bosch offers compact units mostly aimed at point-of-use (like the Bosch Tronic 3000 series for under-sink applications). They’re reliable for what they are intended – for instance, providing instant hot water to a sink or supplementing a remote bathroom. Bosch’s whole-house electric tankless presence is limited (they mostly focus on gas for whole-house because that’s more popular in their main markets).
Energy Efficiency: Bosch’s condensing gas tankless heaters are very efficient – on par with other high-end brands. Uniform Energy Factors in the 0.94–0.96 range are common for their top models. They incorporate a patented stainless steel heat exchanger design and often have features to reduce scaling, which keeps efficiency high over time. Bosch also tends to integrate an automatic burner modulation that aligns heat output closely with demand, avoiding waste. One interesting Bosch feature is their use of OptiFlow combustion management on some models – this system adjusts the gas/air mix dynamically based on altitude and gas quality, which ensures optimal efficiency (and consistent performance) whether you’re at sea level or high elevation. Not all brands automatically adjust for altitude, so Bosch built it in. This is great for efficiency and reliability if you live in, say, Denver or Calgary. Bosch units are all low NOx as well, aligning with environmental standards. And like other condensing units, they require draining condensate, which shows they capture that extra heat from exhaust. With electric models, Bosch’s point-of-use units are 98-99% efficient as expected for electric. The effect of efficiency for an under-sink unit is mostly seen in eliminating standby losses compared to, say, a small electric tank heater that might keep water hot 24/7. Bosch emphasizes that their electric minis save energy by only heating water when needed.
Durability & Build Quality: Bosch’s German engineering heritage comes through in build quality. Their tankless units have high-quality components and a solid feel. For example, the Bosch Greentherm series has a robust heat exchanger and is built to resist corrosion and scale. Bosch sometimes touts features like a fully modulating fan and sealed combustion that prevent internal parts from being exposed to house dust or lint – keeping the unit clean inside over the years. They also often include built-in flush ports or easy connection points for servicing. Bosch gas units typically come with a warranty around 15 years on the heat exchanger and 5 years on parts for residential use, which is standard for high-end units. Electric point-of-use units often have around 5-year warranties. Because Bosch operates globally, their parts distribution is decent – you can find parts through Bosch service dealers or online if needed. Durability-wise, many users in Europe have Bosch units that last well over a decade in regular use, and we expect the same in North America. If there’s any drawback, perhaps Bosch’s support network in NA isn’t as large as Rheem’s or Rinnai’s (fewer certified techs familiar with them), but this has improved as Bosch has focused more on the market. The Greentherm units are designed for long life, with features like built-in scale prevention technology (some models use a proportional flow control or special coating to reduce scale accumulation, meaning fewer maintenance issues).
Tech Features: Bosch has incorporated some intelligent electronics in their newer models. For instance, many Bosch tankless heaters have a digital control panel that displays the temperature and allows for easy adjustments. The Greentherm 9000 series even has Wi-Fi built-in on certain variants – allowing you to control and monitor your heater via a smartphone app. This lets you do things like adjust temperature, monitor energy usage, and receive error alerts remotely. It’s similar to what Rheem and Navien offer in terms of connectivity. Additionally, Bosch’s control system is known for being user-friendly. They often include an LED or LCD display with plain text or code readouts. Bosch’s integrated freeze protection and high-temp limit controls are standard, but they also have an Eco mode on some that can limit the output temperature for saving energy (for example, capping at 120°F by default to save gas, unless you intentionally raise it). A unique Bosch aspect: they sometimes mention their units’ compatibility with solar thermal pre-heating. If you have a solar hot water panel that preheats water, Bosch tankless can accept preheated water (up to a certain temperature) and only top-up the heat as needed. This works because Bosch units can modulate down to very low firing rates. Many tankless can do this, but Bosch explicitly encourages it in their literature, showing their holistic view of home hot water systems. Finally, Bosch’s diagnostic system is quite comprehensive, which helps technicians troubleshoot quickly – it can differentiate between various sensor issues and display specific error codes (which a homeowner can relay to customer service or look up).
Installation: Installing a Bosch gas tankless is similar to other brands. Venting, gas line, water connections all apply. Bosch provides good manuals and has tech support if needed. The Greentherm 9000 series has a nice feature: it can vent using 2” or 3” PVC, and it even allows long vent runs (up to 60 feet), giving flexibility in where you install relative to an outside wall. Bosch units tend to be a bit heavier (due to sturdy build and possibly some additional components) – just a consideration for mounting securely. Most Bosch units are indoor models, but they do have outdoor versions or kits for outdoor installation if needed. If you’re replacing an older Bosch AquaStar or similar, the new ones will likely line up differently, so retrofitting might need re-piping – not a big deal, but Bosch changed designs over time. Given Bosch’s lesser presence, you’ll want to ensure your installer reads the manual if they aren’t used to Bosch; there might be small differences (like how to set altitude adjustments if not auto, etc.). Size-wise, Bosch condensing units are compact but maybe an inch or two larger in one dimension compared to others – still wall-mountable and space-saving. For electric Bosch units, installation is very easy (just water connections and power). Many come with pigtail plugs for 120V smaller units, or need hardwiring for larger 240V units. They’re great for quick installs near a sink.
Eco-Friendliness: Bosch pushes eco-friendly angles like reduced NOx emissions, high efficiency, and compatibility with renewable pre-heat systems. Their gas units having up to 96% efficiency means minimal waste. Also, their auto-adaptation to gas quality (OptiFlow) ensures complete combustion which reduces carbon monoxide and unburned fuel emissions. As a company, Bosch has broad sustainability goals (for instance, Bosch as a whole aims to be carbon neutral in operations). For consumers, using a Bosch tankless can be part of an eco-friendly home – especially if combined with solar thermal as mentioned. Electric Bosch point-of-use can save water (because you don’t run the tap waiting for hot water to arrive through long pipes). Overall, Bosch’s design reducing scale also keeps efficiency high longer, which is eco-friendly in the long run.
Customer Service & Support: Bosch’s presence in NA water heating is smaller than in Europe, but they do have a dedicated support line for Thermotechnology. Reports of customer service vary – some have great experiences with knowledgeable reps, others have had difficulty finding a local service person immediately. It’s a good idea to check Bosch’s website for certified installers or service centers in your area if you’re considering the brand. If one is nearby, then support should be smooth. The brand reputation of Bosch is very high for quality, but not as widespread in tankless specifically. People who have Bosch generally praise its performance and quiet operation. It’s common to see comments like “I chose Bosch because I trust their engineering” – and usually they’re not disappointed. Bosch’s long history in tankless (they acquired/partnered with companies like Junkers in Europe long ago, which had tankless tech, and also had the AquaStar line in the US) means they know what they’re doing. The lower profile in marketing might make it a bit of a hidden gem in North America.
Bottom Line: Bosch is a strong contender for those who appreciate German engineering and are looking for a reliable, efficient tankless heater. It may cost a bit more upfront (and you’ll want to ensure there’s support in your region), but in return you get a well-built unit that is likely to perform admirably and efficiently. Bosch is particularly a great fit for tech-savvy homeowners who might integrate their water heater with other systems (like solar heating or smart home tech) and for those who prioritize quiet, precise operation. We have covered Bosch models in our reviews as well – including breakdowns of their Greentherm units – so do check those write-ups for specific pros and cons (for instance, we note the consistency of temperature as a pro, and perhaps the initial cost as a con, in those reviews).
Stiebel Eltron – German Engineering for Superior Electric Performance
Overview: Stiebel Eltron is a German manufacturer that has been around since 1924, with a long tradition of innovation in electric heating and renewable energy products. When it comes to electric tankless water heaters, Stiebel Eltron is often considered the gold standard. Their Tempra series of whole-house electric tankless units is highly regarded for performance and quality. Stiebel also makes small point-of-use tankless heaters, but it’s their larger units (Tempra and Tempra Plus) that really set them apart in the market. In North America, Stiebel Eltron is a go-to brand for people who want an electric tankless solution that can serve an entire home, especially when gas is not an option. The brand’s hallmarks include excellent performance in electric models, quiet operation, and sleek design.
Performance (Electric): Electric tankless heaters inherently have limitations since they run on the power of your electrical supply. However, Stiebel Eltron has pushed the performance envelope within those limits. The Tempra Plus series features models like Tempra 12, 15, 20, 24, 29, and 36 (the number roughly correlating to the kilowatt rating). The largest model, Tempra 36 Plus, is a 36 kW heater that, in warm climates, can deliver around 4 to 5 GPM of hot water continuously – enough for two showers at once. In colder climates, that output might drop to around 2 to 3 GPM (which would cover one shower and a sink). Stiebel units are known for their Advanced Flow Control feature: this is a proprietary technology where if the demand exceeds the unit’s capacity (say you have too many fixtures running), instead of letting the water temperature drop significantly, the Tempra will slightly reduce the water flow automatically to maintain the set temperature to all outputs. In practice, if someone turns on a third shower and the unit can’t heat that much water at full flow, it will constrict flow a bit to keep the delivered water hot. This prevents those unpleasant lukewarm or cold surprises. Users often praise this feature because it manages the “tankless juggling act” transparently. Also, Stiebel Eltron units can maintain temperature extremely well, within ±1°C (about ±2°F) of the setpoint, thanks to their sophisticated sensors and microprocessor control. Another performance aspect: quiet operation – Stiebel’s electric heaters are virtually silent (no clicking relays; they use Triac switches, which means you don’t hear the unit turning on/off loudly like some cheaper electric units). They also don’t have any venting since they’re electric, so no fan noise either. This makes them great for installations in or near living spaces.
Energy Efficiency: All electric tankless are very efficient (nearly 100% of electrical energy goes into the water as heat), but Stiebel Eltron’s efficiency comes more from not wasting energy on standby and from smart controls that use only the power needed. They are fully modulating: if you only need a little hot water, they might engage just one of their heating modules at partial power, whereas if you need a lot, they ramp up all elements fully. This means they draw only the electricity required at a given moment, which can save you money compared to, say, an electric tank that keeps high wattage elements cycling on and off regardless of actual usage timing. Another aspect of efficiency is durability – Stiebel’s sturdy components mean they maintain their efficiency over time (less risk of element burnouts or degradation that could lower performance). While not efficiency per se, it’s also eco-friendly that Stiebel units enable users without gas to go tankless and save energy compared to an electric tank. Also, if your home is equipped with solar panels or if you have time-of-use electricity rates, an electric tankless like Stiebel can synergize well (you could potentially run it when solar is producing, or, since it only uses power on demand, it doesn’t add base load during idle times like a tank would).
Durability & Build: Stiebel Eltron’s build quality is top-notch. The Tempra units have a sleek polymer casing but internally are built for longevity. They use copper heating vessels with threaded heating elements that can be replaced if needed (though failures are rare if the unit is installed correctly with needed maintenance like occasional inlet screen cleaning). These heaters are designed and made in Germany and undergo rigorous quality checks. Many owners report trouble-free performance for many years. Stiebel backs their tankless units with a 7-year leakage warranty and 3-year parts warranty for residential use. This is actually one of the better warranties for electric tankless units, reflecting confidence in no leaks developing (leaks are one of the worst things that can happen in an electric heater, so 7 years coverage on that is good). Because the units are all-electric, there are fewer “moving parts” – no gas valves or vent motors or anything. This simplicity (no combustion) adds to durability inherently. One thing to ensure durability is proper installation: sufficient wire gauge, correct breaker sizing, and tight electrical connections. If these are done right, the unit should last a very long time. Stiebel also designs their units to be serviceable – elements can be replaced, and the flow sensor or PCB can be swapped if needed (these parts are available through Stiebel’s US distributors).
Features: Stiebel Eltron’s Advanced Flow Control we discussed is a standout feature for user experience. Additionally, Stiebel’s Tempra Plus models include a digital temperature display and dial where you can set the exact temperature you want (from around 86°F up to 140°F, or 30°C to 60°C). This is convenient for adjusting for different uses (maybe you want it a bit hotter in winter, cooler in summer, etc.). The units also automatically adjust to incoming water temperature; there’s no manual adjustment needed seasonally – it’s all seamless. Another feature is safety high-limit switches on the elements to prevent overheating. Stiebel is safety-conscious: their units will shut off if something is wrong (like dry-fire protection if no water is in the chamber). The design ensures no venting required of course (being electric), which is a feature in itself – you can install it virtually anywhere (climate permitting, as it shouldn’t freeze) since you don’t need to run a flue. The form factor of the Tempra is slim and sleek, so much so that some owners mount it in visible areas without concern. Noise-free operation is another “feature” not to overlook – Stiebel themselves advertise “quiet operation” as a benefit. No clicking relays means you won’t even notice when it’s on, aside from the hot water. One could also consider “German engineering” a feature – intangible, but many trust that it’s engineered with precision. Unlike some competitor electric units, you won’t find Wi-Fi or app connectivity on Stiebel heaters – they’ve kept it simple on that front. Generally, electric tankless haven’t gone the smart route as much as gas ones. That said, you typically don’t need an app for these; set it at the unit and you’re done. Stiebel Eltron also provides helpful sizing guides and even offers customer support for sizing – they want to ensure you get the right model for your needs.
Installation: Installing a Stiebel Eltron Tempra requires adequate electrical supply. This is often the biggest consideration. For example, the Tempra 24 Plus (24 kW) will require 2 x 60-amp double-pole breakers (so basically 120 amps at 240V total), and the Tempra 36 Plus (36 kW) requires 3 x 50-amp double-pole breakers (150 amps total). This means your electrical panel must have the capacity (many older homes with 100A service need an upgrade to 200A service if installing the larger units). So, an electrician is almost always involved unless one is very familiar with electrical work. The actual plumbing hookup is fairly straightforward: cold in, hot out, with shutoff valves and perhaps a pressure relief valve (check local code – some places want a PRV on tankless, some don’t). No venting and no gas line simplifies a lot. The unit can be wall-mounted easily and takes up minimal space. Because it’s compact and doesn’t need combustion air, you can put it in a small closet (just not where it can freeze). Another tip: Stiebel Eltron recommends installing a flow restrictor at showers or aerators if needed to keep flow within the heater’s ability in winter – but if you use their sizing, often this is naturally taken care of. They also have an inlet filter screen that should be cleaned occasionally, especially if you have sediment in water – this keeps flow sensor working well and prevents debris from hitting the elements. The install manual is clear and their tech support can help an electrician with any questions. For smaller point-of-use Stiebel units, installation is even simpler: some plug in, others hardwire to a 30A breaker or so, and mount near the sink.
Eco-Friendliness: Stiebel Eltron shines here particularly for those wanting to reduce carbon footprint. If your electricity comes from renewable sources (or you plan to offset usage with solar), using a Stiebel electric tankless can make your hot water generation very green – essentially no emissions on-site and potentially zero emissions overall. Even if your power grid is not fully green, electric tankless can help in specific situations like using solar water preheating or avoiding the standby losses of a tank (less wasted power). Also, because Stiebel’s Advanced Flow Control ensures consistent temperature, there’s less water waste (you’re not fiddling with the mixer to get the right temp constantly, or running water waiting for it to heat up more – the output remains steady). Stiebel’s compactness and lack of venting also reduce material use in installation (no PVC or stainless vent materials needed). Another environmental plus: the long life and serviceability means fewer replacements and less waste over time. On a broader note, Stiebel Eltron as a company invests in sustainable manufacturing and renewable products (they also make heat pump water heaters, solar thermal equipment, etc.), aligning with eco-friendly principles.
Customer Service & Brand Reputation: Stiebel Eltron has a dedicated presence in the US (Stiebel Eltron USA) which provides customer support, and they have a network of distributors and reps. Customers generally report good experiences – the product works so well that they rarely need service, and the company is helpful for sizing or any issues. Because Stiebel Eltron is a premium brand, you might pay a bit more for their unit compared to a lower-end electric tankless, but most agree it’s worth it for the performance and reliability. The brand’s reputation is excellent in the electric water heating segment – often topping “best electric tankless” lists. We’d say Stiebel Eltron has almost a cult following among certain homeowner groups, especially those who are unable or unwilling to use gas. The main caution in reviews is typically making sure you size it correctly (some people try to undersize to avoid electric panel upgrades and then get lukewarm water – not the unit’s fault). As long as you match the unit to your needs, Stiebel Eltron will likely impress. They are indeed a trusted name (they’ve been making tankless heaters for decades, with proven longevity – it’s not a new player or a cheaply made device).
Bottom Line: If you are looking for the best electric tankless water heater, Stiebel Eltron should be at the top of your list. It’s ideal for homes without gas service, or for those who prefer electric for safety or environmental reasons. Stiebel’s units provide a combination of high performance and quiet, unobtrusive operation that is hard to beat in the electric category. Just keep in mind the electrical requirements – you might need an upgrade to fully utilize a large unit. For smaller needs (like a single shower or a remote sink), Stiebel offers smaller models that can be perfect too. We’ve reviewed Stiebel Eltron models on our site, covering real-world performance (for example, in one review we highlight how a Tempra unit handled two bathrooms in a mild climate flawlessly). Check those out if you want even more insight into how these perform in daily life and some installation tips from our experience.
EcoSmart – Budget-Friendly Efficiency with Lifetime Warranty Perks
Overview: EcoSmart is a relatively newer player in the water heating industry (founded in 2008 in the USA). They have quickly gained popularity, especially in the electric tankless water heater market, by offering affordable and compact units that appeal to budget-conscious consumers. EcoSmart’s product line includes whole-house electric tankless heaters, point-of-use electric units, and even some gas tankless models (they have started to branch into gas, including condensing and non-condensing gas tankless units, though they’re best known for electric). The brand is often found online and in stores like Home Depot, and they highlight features like self-modulating technology and a lifetime warranty (on certain models) as big selling points. In short, EcoSmart aims to deliver the tankless benefits (endless hot water, space savings, energy efficiency) at a more accessible price point.
Performance (Electric): EcoSmart’s flagship electric models are the ECO series – for example, ECO 8, ECO 11, ECO 18, ECO 24, ECO 27, ECO 36. The numbers roughly correspond to kW rating and indicative max flow. An EcoSmart ECO 27 (27 kW) can handle around 3 GPM in warm climates (enough for maybe two showers) or about 1.5 GPM in colder climates (one shower). The ECO 36 (36 kW) is their most powerful, meant for larger homes or colder regions, and compares to Stiebel’s high-end (though perhaps a tad less robust in heavy use). EcoSmart units use self-modulating technology, meaning they adjust power draw according to flow and temperature needs, which is similar to how Stiebel and Rheem work. Many users find that EcoSmart units do a fine job of providing consistent hot water for moderate demands. However, some owners in very cold climates or with high flow needs may find that the EcoSmart, if undersized, struggles to keep up – it’s critical with this brand (as with any electric) to follow their sizing guide which considers your incoming water temperature and desired output. One area where EcoSmart sometimes sees mixed feedback is temperature stability when flow rates are near the lower activation threshold or when multiple elements are cycling – a few users report minor fluctuations if the flow is very low or if someone intermittently turns water on/off. But generally, for standard flows like a shower, they hold temperature well within their capacity. EcoSmart units typically activate at around 0.3 GPM flow, which is pretty low and good for low-flow fixtures. They are also compact and lightweight, making it easy to install close to the point of use, which can improve the apparent performance by reducing wait times for hot water at a faucet.
Performance (Gas): EcoSmart has a line of gas tankless water heaters as well (less publicized, but they exist). They offer non-condensing models akin to mid-range units from other brands, and recently some condensing models too. Because EcoSmart’s focus has been electric, their gas line is not as widely reviewed, but the models generally have decent specifications (e.g., mid-size GPM outputs suitable for small-to-medium homes). The gas units likely are OEM from a larger manufacturer (possibly a rebrand from a partner factory) rather than in-house designs. They are meant to round out the product offering for customers who might want an affordable gas tankless. However, if choosing gas, many might still lean towards established gas-focused brands unless EcoSmart’s pricing is significantly more attractive. For the scope of most EcoSmart customers, electric is the main draw, so we’ll emphasize that.
Energy Efficiency: EcoSmart’s electric tankless units are 99% thermal energy efficient – essentially all electric ones share that trait, converting nearly all input power to heat. The advantage EcoSmart claims is that their self-modulating technology can save you up to 50% in water heating costs by only using the energy needed. In reality, any properly functioning tankless does that, but it’s a valid point that if you switch from an old tank to an EcoSmart, you often see noticeable savings, especially if your prior usage caused a lot of standby loss. EcoSmart gas models, if considered, have efficiency ratings typical of their type (around 0.82 for non-condensing, up to 0.90+ for condensing). They are also designed to be low NOx. But again, efficiency is where electric shines: no flue losses, and modular element use. One caveat: electricity can be expensive per BTU, so the cost efficiency also depends on your local utility rates. Still, EcoSmart gives many people in apartments, condos, or smaller homes an energy-saving option that’s an easy upgrade from maybe an underperforming tank or a life of running out of hot water. Also, because EcoSmart units are smaller and simpler, they have minimal standby power draw (just the small LED and control board) – effectively negligible.
Durability & Warranty: Here is where EcoSmart generates both interest and debate. EcoSmart offers a Limited Lifetime Warranty on the electronics, heating elements, and exchanger of many of its electric tankless models for residential use, provided that a licensed professional installs the unit and it is properly registered, and that you replace the components like heating elements when required (and perform maintenance). The warranty can be voided by various things: DIY installation without a licensed electrician/plumber, using it in a non-residential setting (like commercial use has a separate much shorter warranty), or not following maintenance guidelines (e.g., you must periodically remove and inspect elements, replace if needed, etc.). So while “lifetime warranty” is a huge selling point, buyers should read the fine print. If you comply, EcoSmart will send replacement parts under warranty; typically, they do not pay labor. Many users appreciate that they can get free parts many years later if something fails, essentially allowing the unit to be rebuilt instead of replaced. However, some users who didn’t realize these conditions have felt frustrated if something went wrong and they found their warranty wasn’t honored due to, say, self-installation. So, durability-wise: if properly installed (tight electrical connections to avoid overheating of wires, proper flow of water, etc.) and maintained (flush if hard water, clean filters), EcoSmart units can last a long time. They use standard heating elements which are not expensive to replace (not as fancy as Stiebel’s proprietary elements, but easily available). There are reports of occasional sensor failures or element burnouts, which can happen in any electric unit, but the key is those are user-serviceable to an extent. Where some see a downside is that EcoSmart’s build might not feel as heavy-duty; it’s more utilitarian. The company has improved designs over iterations; for example, older models had some plastic flow sensors that people had issues with, whereas newer ones improved that component. The customer service for warranty parts is generally responsive – they will often send you a part if you’re comfortable swapping it, as that’s cheaper than sending a tech. For many DIYers, that’s acceptable. For others who prefer not to tinker, that could be a downside if anything goes wrong outside the labor warranty. In summary, EcoSmart durability is decent given the price, and the lifetime parts warranty is a big plus if you adhere to requirements – essentially, they stand behind the unit’s parts for life, which can make it very cost-effective long term (no buying a whole new heater every X years, just fix it).
Features: EcoSmart electric units come with digital temperature control – typically a simple knob or push-button and a digital display that lets you set output temp in increments (usually 1°F increments). That’s impressive at the price point, giving fine control. They are generally compact – the ECO 27, for example, is only about 17”x17”x3.5” in size and weighs just 11 pounds, making it easy to fit in tight spaces. Installation ease is a feature they promote: many units have bottom-mounted 3/4” NPT water connections that line up for typical replacement of a tank heater’s connections if wall-mounted, and they come with clear instructions. While not “smart” in terms of Wi-Fi connectivity, EcoSmart units don’t really require much fiddling once set. Some models have an Eco Mode (hence the name) which basically is just the normal mode of self-modulation. EcoSmart also sells accessories like remote displays if you want to monitor temp from another room, but those are optional and less common. For gas units, EcoSmart’s features are similar to others (electronic ignition, digital display on some models, etc.), but nothing drastically unique since their gas line is more of a complement to their catalog.
Installation & Size: Most people choose EcoSmart because either they want to try an easy tankless retrofit themselves or they have a small space. EcoSmart electric heaters are ideal for DIY enthusiasts, though to keep the warranty, a licensed pro should sign off. In practical terms, many units get installed by handy homeowners because it’s not overly complicated: mount to wall, connect water lines, run appropriate electrical circuit (which might be the tricky part requiring an electrician). The small size of EcoSmart units means you can put them nearly anywhere – under a sink, in a crawl space, on a wall in a closet, etc. They require clearance for airflow (to keep electronics cool, though they don’t have large fans or anything). With electric, no venting is needed so that simplifies placement. EcoSmart includes helpful mounting brackets and their manuals have templates for drilling holes, etc., making it user-friendly. The weight is minimal – you don’t need studs necessarily; wall anchors often suffice (but if in doubt, mounting on a board attached to studs is always good). For gas EcoSmart, installation would be akin to any tankless: you need proper venting and gas hookup, and that’s likely pro work. Since EcoSmart gas units aren’t as prevalent, ensure there’s support if you go that route. But for the majority who pick EcoSmart, it’s an electric unit for either point-of-use or whole-home in a smaller residence. Electrical installation is the biggest consideration: e.g., ECO 27 needs three 40A breakers (3 x 8 AWG cable), ECO 18 needs two 40A breakers, etc. EcoSmart provides clear electrical requirements. Sometimes, upgrading electrical service is necessary (similar to Stiebel), and that cost should be factored in. Many condo owners or folks in warmer states choose something like ECO 18 or 24 which might fit within a 150A panel without upgrade. So part of EcoSmart’s appeal is understanding what your home can handle and choosing accordingly to avoid extra costs.
Eco-Friendliness: EcoSmart’s name brand is all about eco-friendly hot water. By offering a solution that eliminates standby heat loss and only uses energy when needed, they help reduce waste. The compact manufacturing means less materials used compared to big tanks. Also, because they make tankless accessible cost-wise, more people can adopt this energy-saving technology. If widely adopted, tankless (especially electric ones that can be powered by renewables) could lower the carbon footprint of water heating in many homes. EcoSmart’s focus on small space applications also can encourage point-of-use installs which save water (less time waiting for hot water = less water down the drain). On the downside, an electric tankless uses a lot of current when on, so if the electricity comes from coal or other heavy fossil fuel sources, it can strain the grid at peak times. However, overall energy used is still typically less than a tank that reheats water all day. EcoSmart’s literature often points out things like “save up to 50% off water heating costs” – which ties into using less energy. One more thing: because you can potentially keep an EcoSmart unit running for a very long time by swapping parts, it’s somewhat sustainable in that you’re not scrapping the whole unit frequently.
Customer Service & Support: EcoSmart, now owned by Rheem (as of some years ago, EcoSmart became part of the Rheem family), has decent support infrastructure. Many users mention that calling EcoSmart results in quick troubleshooting and shipment of parts. Others had issues with warranty if conditions weren’t met, but that’s more a misunderstanding than bad support. It’s crucial to register the product and keep proof of professional installation if you want lifetime coverage. EcoSmart also has a lot of online resources – FAQs, sizing calculators, etc. Because of their presence in major retailers, it’s relatively easy to do a return or exchange early on if needed. The brand’s reputation is a bit mixed depending where you look: some love it for the price and performance, others had a bad experience perhaps due to improper sizing or installation. It’s important to filter out reviews where, for instance, someone tried to use an ECO 11 to run two showers – that’s not going to work, and they might then say “this heater is bad” when really it was just the wrong application. Among those who sized and installed correctly, the general sentiment is that EcoSmart provides great valueand they appreciate the endless hot water. In a way, EcoSmart has democratized tankless water heaters by making them more affordable and DIY-friendly. For those on a tight budget, being able to get a tankless for a few hundred dollars and install it with basic plumbing/electrical know-how is empowering.
Bottom Line: EcoSmart is an excellent choice if you’re budget-conscious or have a small space and still want the benefits of tankless hot water. It’s particularly attractive for apartments, condos, vacation cabins, or moderate-sized homes in warmer climates. The key is to choose the right model and have it installed correctly – do that, and you’ll likely be very satisfied. The lifetime warranty (on electric models) is a major plus that can give peace of mind, essentially ensuring your heater can be kept running indefinitely with part replacements. If you value fancy features or absolutely maximum durability, a higher-end brand might suit you better, but you’ll also pay a premium for those. EcoSmart strikes a balance by offering solid performance at a lower cost. Our site includes individual reviews of many EcoSmart models (we’ve covered from ECO 11 up to ECO 36), where we list the pros (like compact size, warranty, cost savings) and cons (like the need for maintenance and possibly reduced flow in very cold weather). Check those out for deeper insight, especially if you’re trying to decide which Eco model fits your specific household needs.
Eccotemp – Portable and Affordable Tankless Solutions for Small Needs
Overview: Eccotemp is an American company (founded in 2004) known for offering compact, budget-friendly tankless water heaters, especially in the portable and outdoor categories. If you’ve ever browsed for a portable propane shower or a small RV water heater, you’ve likely come across Eccotemp. They specialize in tankless units that are great for camping, RVs, off-grid cabins, food trucks, or small homes. Eccotemp produces both gas and electric models, but they’re most famous for their LP/propane portable units (like the Eccotemp L5, L10, etc.) and small indoor gas units (like the Eccotemp i12, FVI12, or the larger 20H/45H series). The key appeal of Eccotemp is that they make tankless hot water very accessible – their units are typically much cheaper than big-brand whole-house models, but are aimed at lower flow applications or niche uses.
Performance: Eccotemp’s product range can be divided into portable units and more permanent units:
• Portable Propane Tankless (Outdoor Use): Models like the Eccotemp L5, L7, L10 are designed to be hung on a hook or carried and connected to a small propane tank and garden hose. The L5, for instance, provides about 1.5 GPM of hot water – perfect for a quick outdoor shower or washing off gear, but not high enough for multiple fixtures at once. These units are battery-ignited (using D-cell batteries to spark, since often you won’t have electricity when camping) and they activate when water flows. They require minimal water pressure (~20-30 PSI) to run, so even gravity-fed water or a small pump works. Performance-wise, they can raise water temperature by roughly 30-40°F at max flow, which is sufficient if your source water isn’t too cold. People use them for outdoor showers, horse stables, camping, etc. They give you the luxury of hot water anywhere, which is a big deal for off-grid living or recreation.
• Small Indoor Tankless (Gas): Eccotemp offers models like FVI12 (a 3.6 GPM natural gas or propane indoor unit), i12(similar capacity but with a nicer glass front panel and digital display), and larger ones like 20H (5-6 GPM) and 45H (6-7 GPM) which are outdoor mount units for small homes. The FVI12/i12 are often used in tiny homes or as point-of-use for a bathroom or small cabin. They can typically support one shower at a time. They have electronic ignition (need plugging in to standard 120V for power) and simple controls. The 20H/45H series are more like conventional tankless sizes (the 45H is around 140k BTU, which in warm climates can do 3 fixtures, but in cold climates maybe 1-2). However, Eccotemp’s larger units are still considered more “entry-level” for whole-home systems – they’re less expensive but perhaps not as feature-rich or robust as a Rinnai or Rheem. They do, however, get the job done for many. For example, a family in a mild climate might use an Eccotemp 20H for two bathrooms with some care not to run both showers and washer exactly at the same time – that might be acceptable given the lower cost.
• Electric Units: Eccotemp also has some electric models like the Eccotemp iE series (like iE-11, iE-18, iE-27 corresponding to kW). These are similar in concept to EcoSmart’s electric lineup, aimed at point-of-use or small whole-home use. They haven’t been as popular or widely reviewed as EcoSmart or Stiebel, but they offer an alternative in the budget electric category.
In terms of performance, Eccotemp units typically have simple controls for temperature (on gas models, a gas flow knob and a water flow knob to roughly set temperature – not as precise as a digital thermostat, except the i12 which has a digital display). The portable ones are especially straightforward – they basically ensure the burner comes on when you open a water tap and goes off when you close it. One performance area to note: because Eccotemp units are budget-oriented, they might not have advanced modulating valves. Some units have only 2 or 3 burner stages rather than fully variable gas flow, which means there can be some slight temperature drift if flow changes drastically. The portable units, for instance, modulate but you typically set a flame level and it’s a bit of a manual adjustment to get the temperature you want each time based on incoming water temp and flow. In contrast, high-end units automatically adjust. But given their use cases (like showering outdoors), a little manual tweak is fine for most users.
Durability & Build: Eccotemp’s build quality is decent for the price, but it’s not aiming for 20-year lifespan like some premium brands. The portable units (L5/L10) have galvanized or painted steel bodies that hold up outdoors for a while, but if left in harsh conditions long-term, they might rust or corrode. Many people use them seasonally and store them indoors when not in use, which greatly extends their life. The indoor units have more plastic in the exterior design (the i12 has a sleek black glass front panel which actually looks quite modern). Internally, they use standard components but perhaps not of the highest grade (for example, the heat exchanger might be copper but slightly thinner, or other parts might be aluminum where a premium brand uses brass, etc.). That doesn’t mean they’ll fail quickly, but likely an Eccotemp may not last as long under heavy daily use as a more expensive unit. However, many users report getting years of reliable service, especially if they maintain it (flush out scale, ensure it’s not exposed to freezing, etc.). One should consider that Eccotemp units are often bought for occasional or light use (like cabins, weekend homes, etc.) and in those scenarios, they can last quite a long time because they’re not being pushed constantly.
The company provides warranties typically around 1 year for the portable units and a bit longer (maybe 2-5 years) for some of the indoor models (depending on the part – often 10 years on heat exchanger, 5 years on parts for the larger models, which is actually similar to mid-tier brands). But the hitch is that Eccotemp might require you to pay shipping or other handling for warranty service, and sometimes it’s easier for a consumer to just replace a unit at that price point if something major goes wrong after a few years.
Unique Features: Eccotemp’s niche is portability and off-grid use. The L5 and its siblings stand out because they ignite with batteries and can operate with low pressure and flow, making them ideal for camping setups. They often come with adapters to connect to garden hoses and attachments like showerheads. This is something major brands usually don’t make. Also, Eccotemp’s small form factor indoor units (like the FVI12) have very small minimum BTU inputs, meaning they can heat a trickle of water – good for low-flow fixtures. They might not have fancy Wi-Fi or recirculation or anything, but for many this simplicity is a boon (less to break). The newer indoor models like the i12 have a nice LED display showing temperature which is more than some competitor units in that price range offer (which might just have knobs). Additionally, Eccotemp has tried to cater to aesthetics a bit with that black tempered glass front on i12 – so if it’s in view, it doesn’t scream “ugly water heater”.
One downside in features: many Eccotemp units (especially older ones) did not have a direct vent sealed combustiondesign for indoor – for example, FVI12 draws air from the room and vents out a small chimney (so you need proper ventilation in the install area). Newer models like their 20H/45H are outdoor mount, so you avoid indoor venting by placing it outside. If you need indoor sealed combustion, Eccotemp’s offerings are limited at the moment; they expect you to mount it outside or in a ventilated space for larger ones. The portable ones must only be used outside for safety (they’re not vented at all except the open air).
Installation: For portable Eccotemp units – installation is virtually none: you hook up a propane tank and water source when you need it. They even have a handle on top for carrying. For permanent installs, Eccotemp often appeals to DIYers. People with some handyman skills often install the small indoor models themselves, as they can rig up the vent (usually a short section of stainless steel vent pipe out a wall), connect to a propane tank or natural gas line (though gas work should ideally be done by a pro), and attach water lines. Because these units are relatively low BTU (FVI12 is ~50k BTU), some use them on small propane tanks or existing smaller gas lines. But caution: always ensure your gas supply is adequate in pressure and volume for safe operation. Eccotemp’s manuals and support can guide on that.
Size-wise, Eccotemp units are very compact. For example, the L5 portable is only about 16” tall, 11” wide, 4” deep. The FVI12 indoor unit is about 24”x15”x5”. They can easily fit in tight spots, which is why tiny home builders often use them. They do need certain clearances (especially to combustibles around the flue or if indoor the top gets hot). The outdoor 20H/45H mount on an exterior wall and look like a small box (though not as slim as say a Rinnai, but still not huge).
Eco-Friendliness: Eccotemp’s contributions here are primarily in enabling off-grid living and reducing waste by giving a tankless option instead of heating a whole tank. However, many of their portable units are not the most efficient (they’re not condensing or anything), but since they’re used intermittently, the overall fuel usage can be quite low. The fact that they allow hot water on demand means you might use less propane than if you were heating a kettle or a big tank with a pilot light constantly. They also allow people in remote areas to avoid using generators for power (battery ignition means no grid power needed for the portable ones). Their gas units are mostly low NOx now by compliance. Electric Eccotemp units share the efficiency of other electric ones, and can allow a quick solution to heat water at the point of use which can avoid long plumbing runs (which waste water and heat). So, in summary, Eccotemp helps make efficient hot water more accessible but doesn’t specifically push the envelope on efficiency technology.
Customer Service & Reputation: Eccotemp’s customer service is generally helpful, especially for troubleshooting the portable units. They know a lot of non-professionals use their products, so they often provide good step-by-step help. Replacement parts like diaphragms, sensors, etc., for the portable units are available and the company sometimes sends them if under warranty. There is a fairly active online community of Eccotemp users (especially in off-grid forums) who share tips on maintenance (like how to prevent scale or clean the burners). The reputation of Eccotemp is that of a budget brand that largely delivers on what it promises: it won’t compete with high-end units in a McMansion, but for a camper, cabin, or small home it’s a lifesaver for the price. If one goes in with the right expectations, they’re usually happy. Typical praise: “I have hot water at my remote cabin thanks to Eccotemp, it’s been great for years.” Typical criticism: “My unit started giving trouble after X years” – but often that’s fixed with some part replacement or cleaning, which again for many DIY folks is acceptable. The company has been around long enough that it’s not fly-by-night; they continue to update models and release new ones (like the addition of the 45H for bigger needs).
Bottom Line: Eccotemp is the go-to brand if you need a small, portable, or low-cost tankless water heater for light or specific uses. It’s perfect for outdoor adventures, off-grid cabins, tiny homes, and budget installations where top-tier performance is not required. For a full household with high demand, Eccotemp can work in warmer areas or smaller homes, but it’s not intended for heavy-duty multi-shower use in cold climates. Think of it as the “everyman’s tankless” – affordable, easy to use, and extremely handy in the right scenario. We’ve reviewed several Eccotemp models on our site (like the L5, L10, FVI12), detailing the pros (like portability, price) and cons (such as the need to protect from freezing, or limited flow) for each. If you’re considering Eccotemp, check those reviews for additional insights and real-world usage stories – they’ll help set your expectations and give tips on getting the most out of these units.
Camplux – Portable Propane Prowess and RV-Friendly Design
Overview: Camplux is a brand that has made a name for itself by focusing on portable and outdoor tankless water heaters, quite similar in concept to Eccotemp’s portable line. Camplux devices are widely sold online (Amazon, etc.) and cater to those who want hot water in remote or mobile settings – think camping showers, RVs, outdoor kitchens, barns, etc. They also offer some indoor units and small electric units, but their standout products are the portable propane tankless water heaters which are known for being lightweight, easy to use, and capable of working with low water pressure. Camplux essentially competes in the same space as Eccotemp’s outdoor units, often with very comparable specs and designs.
Performance: Camplux portable propane heaters come in various capacities, typically rated by flow in GPM and BTU. For example, Camplux 5L (often referred to as 2.64 GPM, 68,000 BTU) and Camplux 10L (around 3.0 GPM, ~82,000 BTU). These units ignite with batteries (2 D-cells) and only require around 3-5 PSI of water pressure to start – which means even a gravity-fed water source or a small 12V pump can make them work. This is a big selling point: Camplux is often praised for working in scenarios where other heaters might shut off due to low pressure. Once ignited, they can raise water temperature significantly (you can adjust flame and flow to get hotter water at lower flow or vice versa). The 2.64 GPM model, for instance, can comfortably allow a warm shower or washing station; if water is very cold, you’d lower flow a bit to get it hot enough, which is typical for these portables. They include an attached showerhead in many packages for convenience.
Camplux also has some larger outdoor models like the Camplux 16L/6.86 GPM Outdoor tankless (around 180,000 BTU) which is meant to be mounted outside a home or cabin, serving as a permanent water heater for a small household. It’s like an entry-level whole-home unit (suitable for 1-2 showers in warm climates). For indoor use, they have models like Camplux 12L (3.18 GPM) Indoor, which is similar to Eccotemp’s small indoor offerings. These have digital displays and are more for single-point or low-demand whole-home scenarios.
One aspect where Camplux shines is ease of use: connect water and gas, insert batteries, and it works – the portable ones turn on with water flow and off when it stops, thanks to an internal water flow sensor and micro-switch. For performance in an RV or camping environment, having instant hot water in that context feels luxurious, and Camplux delivers that reliably as long as your propane isn’t running low and your water source is adequate. They also have built-in protection like a tilt switch (shuts off if the unit is tilted too much, to prevent accidents) and a flame failure device.
Durability & Build: Camplux units are built to be lightweight and cost-effective. The portable units have a stainless steel or painted body, with exposed components like the gas knob, water knob, and battery housing. They are meant to be used outdoors; like others, they shouldn’t be used or stored in freezing conditions with water in them (freezing will crack the exchanger). The durability is generally good for seasonal and moderate use. Many people have used a Camplux portable for years during summers or camping trips without issue. If you left one outdoors permanently exposed to the elements, you’d likely see wear (rust, debris clogging burners, etc.), so some care is needed – either shielding it from rain or bringing it in when not in use for long periods.
Camplux indoor units and the larger outdoor ones have more robust housings and incorporate things like anti-freeze protection (built-in electric heating elements to protect the unit – but that requires plugging them in). The quality is decent, though as a more value-focused brand, they might not have the absolute longevity of high-end brands under heavy daily use. However, since Camplux often targets smaller scale use, they likely last a satisfying duration for those consumers. Camplux provides around 1 year warranty on portable units, and possibly a bit more on some indoor models (maybe 1 year parts, 3 year heat exchanger, depending on model – this info should be checked per model as it varies).
One thing to mention: because Camplux is used by many off-grid folks, maintenance like cleaning the water filter screen or draining it after use is key to durability. Those who maintain it find it lasts; those who leave water in and let it freeze, obviously, will lose the unit.
Features: Camplux’s key features revolve around usability in remote situations.
• Low Water Pressure Start: Many models advertise working with as low as 3.0 PSI (some say 3.0, others around 10 PSI; effectively, they work with gravity or a small pump). This is accomplished by using a small internal pump or just a sensitive flow sensor combined with low restriction through the unit.
• Multiple Protection Systems: Overheat protection (it’ll shut off if water temperature exceeds a certain limit, like 167°F, to prevent scalding), flame failure protection (shuts gas if flame goes out), and anti-freeze drain plug (you can manually drain water out to avoid freezing damage). The portable ones often have that tilt switch as well for safety if it tips over.
• Compact and Lightweight Design: The 5L model weighs only around 10 pounds. That portability is a feature in itself. They also include handy bits like a carry handle and sometimes even a showerhead and hose in the box.
• Simple Controls: Typically, there’s a summer/winter switch (to reduce burner use in summer so water doesn’t overheat) and gas/water flow knobs to control temp. Some of the more permanent models have a digital thermostat for precise control.
Camplux also has a small line of electric mini-tank water heaters (like 1.3 gallon, 2.5 gallon mini-tanks that plug in) for under-sink use – not tankless, but just to note their product range includes those. Plus, they have some small electric tankless units (3.5 kW, etc.) for single sinks – these are akin to other brands’ point-of-use heaters.
Installation: For portable units, installation is virtually plug-and-play: hook to a propane tank (often via a regulator hose included), attach a water source (garden hose quick-connect typically included), and hang it on a tree, RV, or wall using the handle or bracket. Within minutes you can have hot water out in the wild. They really focus on that quick setup.
For permanent outdoor units (like their 6.86 GPM), you mount it to an exterior wall and connect to the gas line and plumbing. These need proper gas line sizing and perhaps a professional if you’re not comfortable with gas plumbing. They vent from the front (like a tankless designed for outdoor), so you must ensure it’s in an open-air area.
For indoor units, like the 12L, installation is similar to other indoor tankless: you’ll need to run a vent pipe (usually included a short piece that goes through the wall, these units often use smaller diameter vent like 4” double-walled for the small ones). You also need proper gas hookup and water hookup. These indoor units should be installed by someone knowledgeable, as venting gas appliances is critical for safety.
Size and weight: Camplux portable units are similar in size to Eccotemp ones – small and manageable. Indoor units are also compact (the 12L is about 24” tall, 14” wide, 6” deep). They’re aesthetically okay – often white metal cabinets that look fine in a utility area.
Eco-Friendliness: Camplux, by enabling on-demand heating in remote locations, can help avoid wasteful practices (like heating water over a fire or using large generators). On-demand nature is eco-friendly in that you only burn propane when needed. They also allow people to use less water by providing warm water faster at remote points (instead of carrying hot water from somewhere else, etc.). Propane is a relatively clean-burning fuel (low carbon, low soot). The efficiency of these portables is moderate (they’re not condensing, so more heat is lost than in a condensing unit, and no Energy Star ratings here), but in the context of occasional use, fuel consumption is not huge. For a permanent Camplux outside unit, efficiency is on par with other standard tankless (~80-85%). They meet low NOx requirements in most cases.
One could say that making tankless technology available for outdoor lifestyles encourages an appreciation of sustainable practices (like taking shorter showers off-grid, since you’re limited by water supply, etc.). Camplux doesn’t specifically boast eco credentials beyond that.
Customer Service & Reputation: Camplux being a relatively newer brand (last several years in prominence) often sells through retailers, which handle returns and such. The brand does have a customer support line/email that users have had varying interactions with. Some report quick replacements when things were faulty out of box. Others mention that documentation could be better (sometimes manuals are clearly translated, but they get the point across). The community knowledge is helpful; many RV forums and tiny house blogs mention Camplux units.
The reputation of Camplux among users is generally positive for the portable units – they do what they’re supposed to, provide hot water when camping. People love the convenience and wonder how they camped without it. For heavier use units, there’s less broad feedback; those who have the big ones often compare them to similar budget options and find them adequate.
In comparison to Eccotemp, Camplux is often seen as very similar – some prefer one over the other based on small differences (Camplux sometimes is a tad cheaper and has a slightly different style case). Both are Chinese-manufactured, but design and support are based in their respective companies. Camplux specifically markets heavily to the outdoor adventurer niche, even showing images of poolside showers, dog washing, etc.
Bottom Line: Camplux is an excellent choice if you need a portable, easy-to-use tankless water heater for outdoor or off-grid purposes. It brings a level of comfort (hot showers, etc.) to camping and remote living in a very accessible way. It’s also a viable budget solution for small homes, RVs, or workshops that need hot water without investing in large systems. However, like any budget brand, it’s best suited for light to moderate use. If you have a continuous, daily high demand, a more robust brand might serve longer, but for intermittent or lower volume usage, Camplux is a champ. We’ve reviewed some Camplux models on our site (especially the Camplux 2.64 GPM portable unit), highlighting the pros (incredible portability, fast hot water, low pressure operation) and cons (must be used safely outdoors, not as durable as permanent units under heavy use). Check those reviews for details on setup experiences and any tips to keep them running smoothly (like using a pump with a filter to avoid debris, draining after use, etc.).
Marey – Budget-Friendly Tankless for Homes and Travel
Overview: Marey is a brand that has been producing tankless water heaters for quite some time (founded in 1955, originally in Puerto Rico). They offer a range of affordable tankless water heaters in both gas and electric, targeting customers in the Americas, particularly in the Caribbean, Latin America, and North America. Marey might not be as widely recognized as Rheem or Rinnai in the US, but it has a strong presence in the budget tankless category. Many of their products are comparable in target market to EcoSmart (for electric) and Eccotemp/Camplux (for small gas units). They have small gas units ideal for apartments or cabins, and also some larger ones for whole-home use. Marey is often sold through online retailers and sometimes in stores catering to off-grid or budget home improvements.
Performance: Marey’s gas tankless models, like the Marey GA5, GA10, GA16 etc., are typically natural draft, non-condensing units that don’t require electricity to ignite (many use battery or hydropower ignition). For instance, the Marey GA10LP can deliver about 3.1 GPM of hot water, suitable for a shower and sink concurrently in warm climates. Their GA16 (also known as 4.3 GPM) can handle a bit more, maybe two showers in a warm region or one at a time in cooler region. These units have simple mechanical controls. A big appeal in certain markets (like areas with unstable power) is that some Marey models use hydro-generators or batteries for ignition – so they ignite with the water flow using a tiny built-in water turbine that generates a spark, meaning no external power needed. This is great in places with frequent outages or for off-grid homes with water pressure but wanting to avoid using up battery bank for hot water.
Marey also has some indoor forced-vent units (like Marey 2.0 GPM tankless, which is a smaller vented unit requiring 120V, sort of an indoor safe model for small uses) and some larger units like the Marey 3.1 GPM and 4.3 GPM (which are naturally vented, needing flue to open air). Some of their units are essentially rebranded generic units, but Marey has been involved enough to refine them for their markets.
On the electric side, Marey sells units like the Marey ECO line (ECO110, ECO150, ECO180, ECO210, ECO270 etc.), which ironically is named similar to EcoSmart’s but is a different line. These are electric tankless with digital controls and self-modulating features. Their performance is akin to other electric units of same kW – e.g., ECO270 is 27kW, handles about 2-3 GPM depending on inlet temp, suitable for a small house in Florida or a single bathroom in a colder climate. They also have basic electric units (like Marey Power Pak 5L, which is a very small single-point tankless, or the Marey Mini Tank 2.5 gallon units).
Marey’s performance in real use: gets generally positive notes for output matching expectations. They do need proper sizing like any tankless. Some older reviews mention needing good water pressure for certain models to activate fully (especially the hydro ones need a certain flow to spin up the generator). But overall, if used within their capacity, they provide endless hot water as expected.
Durability & Build: Marey’s products are budget-oriented, so while they are generally reliable, they may not last as long as premium units if under heavy continuous use. Many Marey gas units have minimal electronics (which can be a plus for durability – fewer things to break). The heat exchangers are usually copper. Build quality is similar to other lower-priced units: acceptable, though things like the knobs or the outer case might feel lighter or less sturdy than high-end models.
One area to watch is maintenance: for example, the hydro-generator ignition units have a little turbine that can get clogged if your water isn’t clean, so they recommend cleaning the water filter regularly. If you do so, it can last many years. Some users have reported 5-10 years of use on Marey gas units in mild climates (with occasional part replacements like a diaphragm or sensor), which is decent.
Marey offers warranties generally around 5 years on heat exchangers and 1-2 years on parts for many models (with conditions). This is slightly shorter than high-end brands but typical for budget models. Also, historically Marey’s support in certain regions has been okay – they have an office in Florida for US support. They often can send parts if needed.
Notable Features:
• No Electricity Needed (for many gas models): This is a key selling point. Models like GA5, GA10, GA16 use either batteries or a built-in water-driven ignition. So if you’re off-grid or in a place with no outlets near the unit, these work great. That’s one reason Marey is popular in islands and Latin America where older homes may not have an outlet for a water heater or people rely on gas during power outages.
• Compact Size: Marey units are typically compact. Even their larger GA16 is relatively small (wall-mounted box). They fit easily in apartments or small homes where a big tank was impractical.
• Digital Controls on Electric Units: The Marey ECO electric series has an LCD and push buttons to set temperature, similar to EcoSmart. It makes them user-friendly.
• Affordable Replacement Parts: Marey sometimes sells parts kits or their support can direct you to replacements for things like the ignition pins, sensors, etc. This way, a handy owner can fix minor issues without buying a new heater.
Installation:
Gas Marey units (especially those requiring no power) often are natural draft, meaning they must have a flue pipe venting upwards like a chimney. They draw air from the installation room. So, you have to install them in a well-ventilated area or outdoors (some mount them in sheltered outdoor areas) or treat them like a furnace with a vertical flue. This can limit where they can be safely installed (not in bathrooms or bedrooms; usually in a service area or outside porch). Installing them is straightforward though: hook up gas, water in/out, vent it out. Because many don’t have blower fans, venting must be more strictly vertical and short if possible (since exhaust relies on natural rise of hot air). This is old-school style, similar to how old tank water heaters vent.
The electric units install just like other electric tankless – wall mount, connect appropriate gauge wires and breakers, and water lines.
Marey also explicitly designs some units for mobile use or propane tanks (like they provide kits to connect to standard BBQ propane tanks, and some say they are okay for food trucks, etc.).
Eco-Friendliness: Marey’s contribution here is giving an alternative to tanks, thus saving energy by not maintaining standby heat. In regions where electricity is expensive or unreliable, using a tankless gas unit can be more eco-friendly than an inefficient electric tank that might be used otherwise. Also, the hydro-ignition means no pilot light (older tank heaters wasted gas with pilots; Marey lights only when needed). They are low NOx nowadays by design to meet various regulations. The electric ones, like others, can be powered by renewables, so they fit into green solutions.
Customer Service & Reputation: Marey has a somewhat mixed bag of reviews historically, partly because earlier models in decades past maybe had issues or because user error/installation issues can lead to negative reviews. However, those who understand what they’re buying and install correctly often find Marey to be a cost-effective and reliable solution. The brand has a strong foothold in places like Puerto Rico, other islands, and rural areas because of their no-electric ignition units.
One challenge can be finding a contractor familiar with Marey if you need service, as many plumbers might not recognize the brand compared to Rheem etc. But the units’ simplicity often means less need for specialized service – a general gas appliance technician can figure it out.
People who use Marey tend to cite value for money as the big pro. They are happy to get a tankless experience at a fraction of the cost. Some caution that you must follow the maintenance guidelines and understand the limits (for example, a GA10 is not going to run two showers, don’t expect it to).
Marey’s customer support has improved with their Florida base; they do have phone and email support and sometimes even answer questions on forums.
Bottom Line: Marey tankless heaters are a great pick if you’re looking for a budget-friendly, basic tankless unit and especially if you need one that doesn’t rely on electricity. They are well-suited to small homes, cabins, or even RV/boat setups (with proper venting) where you want endless hot water but can’t invest in high-end systems. They provide the core benefits of tankless (no tank, endless hot water, energy savings) at a lower upfront cost. However, they might require a bit more involvement from the user in terms of maintenance and understanding the installation environment. If you treat them well, they’ll serve you well in return. On our site, we’ve reviewed a few Marey models, noting the pros (affordability, no power needed for some, decent performance in warm climates) and cons (manual venting needs, not ideal for high flow in cold areas). If Marey is on your radar, those reviews can give you an idea of real user experiences and tips for installation (like ensuring enough water pressure and proper gas line sizing, which sometimes get overlooked).
Now that we’ve gone through each major brand in detail, let’s draw everything together in a convenient comparison table and then wrap up with some guidance on choosing among these brands.
Comparison Table of Major Tankless Water Heater Brands
To help visualize the differences between these brands, the table below summarizes key characteristics and highlights:
| Brand | Primary Fuel Types | Notable Strengths | Potential Drawbacks |
|---|---|---|---|
| Rinnai | Gas (Natural/Propane) | High performance (up to ~11 GPM models); excellent build quality; 15-year heat exchanger warranty; advanced features (Wi-Fi, recirculation logic) in newer models; wide availability (Home Depot, etc.) | Higher upfront cost; professional installation recommended (needs proper venting & gas line); some models require extra kit for Wi-Fi or recirc; not designed for off-grid (needs power for ignition) |
| Navien | Gas (Natural/Propane) | Ultra-high efficiency (all condensing, ~95%); built-in recirculation pump and buffer tank on premium models for instant hot water; compact design; advanced tech (Wi-Fi via NaviLink, dual stainless exchangers) | Premium pricing; installation can be complex (condensate drain, dedicated vent kit for some); fewer retail outlets (typically through dealers); requires careful maintenance (more complex internals) |
| Noritz | Gas (Natural/Propane) | Innovative and customizable lineup; high quality components (copper/stainless exchangers); some models easy to install (top connections, flexible venting options); long lifespan (up to ~20 years); eco-friendly focus (low NOx, future-ready for gas mixtures) | Can be pricier than other budget options; many models sold via professional channels (less DIY); limited electric offerings (gas-only); requires professional install and venting in most cases |
| Takagi | Gas (Natural/Propane) | Excellent safety features (overheat cutoff, etc.); user-friendly simple design; reliable for small-to-medium homes; generally more affordable than Rinnai/Navien; no power needed for some models (battery ignition available) | No integrated Wi-Fi or smart features; not ideal for very large demand or colder climate high-flow (some models struggle with multiple simultaneous showers); availability mainly through distributors (though some sold under A. O. Smith brand in stores) |
| Rheem | Gas & Electric | Widely available and affordable; offers both gas and electric units (one-stop brand); good efficiency (Energy Star models); smart features via EcoNet app on higher-end models; strong support network and parts availability; multiple sizes for various needs | Some gas models have lower flow rates than competitors’ top models; mixed reviews on longevity in heavy use (1-year labor warranty); electric models may require significant power (panel upgrades for larger units) |
| Bosch | Gas & Electric | German engineering precision; very consistent hot water output (intelligent controls); high build quality (anti-scale tech, robust exchangers); quiet operation; indoor/outdoor models available; strong efficiency (condensing gas ~96%) | Higher price point on some models; smaller selection in NA market; fewer technicians familiar with Bosch in some areas; app/Wi-Fi on limited models (only select high-end units) |
| Stiebel Eltron | Electric | Top-tier electric performance; extremely quiet (no relay clicks or noise); Advanced Flow Control prevents temperature drops; sleek, compact design; high reliability and support; ideal for homes without gas – can supply whole-house hot water if properly sized; 7-year leak/3-year parts warranty (best in electric class) | Requires very high electrical amperage for large models (may need panel upgrade to 200A+); no gas options (so not an all-fuel brand); higher initial cost than budget electric brands; limited smart home integration (no Wi-Fi, but not usually needed) |
| EcoSmart | Electric (and some Gas) | Budget-friendly electric units with good performance for price; compact size ideal for apartments/small spaces; Lifetime warranty on electronics/elements for original owner (if professionally installed); digital temperature controls; easy DIY-style installation (if you have electrical know-how); wide availability (online and retail) | Lower flow capacity in cold climates (electric limitations) – must size carefully; components may require periodic maintenance (and warranty depends on pro install and maintenance); some reports of shorter lifespan if not maintained (sensor or element replacements may be needed over time); gas models exist but less proven/popular than electric line |
| Eccotemp | Gas & Electric | Portable and off-grid specialty – great propane camp/RV units with battery ignition (hot water anywhere!); low-cost small gas heaters for cabins, etc.; simple to use and install; perfect for outdoor showers, camping, food trucks; compact designs; replacement parts available and units are user-serviceable; caters to DIY crowd and off-grid living (no power needed for many models) | Not designed for heavy-duty whole-home use (limited GPM; larger models are entry-level in performance); durability is decent but not on par with premium brands (especially under continuous use); warranty shorter (1 year standard); requires proper ventilation for indoor models (many are outdoor only or natural draft) |
| Camplux | Gas (Propane) & Electric (small) | Ultra-portable propane heaters – very popular for camping, outdoor events, remote showers; extremely low water pressure required (works with gravity or 12V pump); quick setup and lightweight; includes safety features for outdoor use (tilt and flame sensors); also offers small indoor units for sheds, barns, etc.; budget-friendly pricing | Strictly outdoor use for portable units (can’t use inside a tent/RV except with proper venting); mainly suited for single-point use (1 shower or faucet at a time); longevity can suffer if left in harsh weather (best to drain/store when not in use); indoor models are basic (lack advanced controls beyond digital temp) |
| Marey | Gas & Electric | No-electric-needed gas options – ideal for regions with power issues or off-grid (hydro or battery ignition); affordable solution for tankless, especially in small homes/apartments; has been in business for decades (experience in tropical climates); straightforward design that many general plumbers can work on; electric models provide another budget tankless choice with digital controls | Many gas models are natural draft (need vertical flue, not sealed combustion) which can limit installation locations; build quality is adequate but not luxurious (some components may wear and need replacement over time); customer support is improving but brand is still lesser-known to installers in some areas; must ensure sufficient water pressure for hydro ignition models to work optimally |
Notes: All these brands produce on-demand hot water heaters that save energy by heating water only when needed. Proper sizing is crucial: a unit must match your peak hot water flow requirements and climate (incoming water temperature). Gas units generally offer higher flow rates for whole-house use, while electric units are often best for smaller applications or warmer regions unless you have a robust electrical supply. Installation costs and complexityvary: gas units require venting (except outdoor models) and often need pro installation to ensure safety and warranty, whereas many electric units and portable propane units can be installed by skilled DIYers or with minimal professional help. When evaluating warranties, note the fine print – some “15-year” or “lifetime” warranties require professional install and regular service.
Choosing the Right Brand and Final Tips
With a solid understanding of each brand’s strengths and specialties, how do you decide which tankless water heater brand is best for you? Here are some considerations to guide your decision:
• Fuel Type and Availability: First, determine whether gas or electric makes sense for your situation. If you have natural gas or propane readily available and need to support multiple fixtures, a gas tankless (Rinnai, Navien, Noritz, Takagi, Rheem, Bosch, Marey Gas) is likely the way to go. If you have no gas line (or want to leverage solar panels or avoid fossil fuels), look at electric options (Stiebel Eltron is top-tier, EcoSmart and Marey offer budget-friendly electric choices, Rheem has both, Bosch electric for point-of-use). For off-grid with no electricity, consider brands like Marey (hydro-ignition gas) or Camplux/Eccotemp (battery-ignition propane) to get hot water without grid power.
• Household Hot Water Demand: Think about how many showers and appliances you’ll run simultaneously at peak. For a large home with high demand, premium gas brands like Rinnai, Navien, or Noritz have high-flow models and the reliability to handle heavy use. For a small home, apartment, or single-shower scenario, an electric unit from Stiebel or EcoSmart could be sufficient (especially in warmer climates), or a mid-size gas unit from Takagi or Rheem. For point-of-use (say you just want to add hot water to a garage sink or an outdoor shower), a smaller electric tankless or a portable gas unit from Camplux/Eccotemp might be perfect.
• Budget Constraints: All these brands have different price points. If you’re on a tight budget but still want to go tankless, EcoSmart and Marey (for electric) and Eccotemp, Camplux, Marey (for gas) offer affordable units. They might not have the longevity or advanced features of pricier brands, but they do the job. If budget allows, investing in a higher-end brand (Rinnai, Navien, Noritz for gas; Stiebel for electric) often pays off in longer life, better support, and sometimes more efficiency.
• Installation Considerations: Are you planning to DIY or hire a pro? Some brands are more DIY-friendly than others:
• DIY-Friendly: EcoSmart (electric) is straightforward if you’re comfortable with electrical work. Camplux and Eccotemp portables are extremely easy to set up for temporary use. Marey’s simple gas units can be DIY’d by experienced folks (though gas work caution is always advised). Rheem electric units come with good instructions and support.
• Professional Install Recommended: Rinnai, Navien, Noritz, Takagi, Bosch, and high-capacity Rheem gas units should be installed by professionals to ensure proper venting, gas supply, and warranty protection. Stiebel Eltron electric, given the power involved, often requires an electrician to run the appropriate wiring.
• If you rent and can’t do major modifications, consider non-venting needed solutions: e.g., an electric tankless (no flue) or a portable gas unit used outside (no permanent install).
• Climate and Environment: In cold climates, if going electric, lean towards the most powerful/high-end electric (Stiebel Eltron or EcoSmart’s larger models) and be prepared for reduced flow in winter. Gas units handle cold water input better, but you might need a higher BTU model or even multiple units in parallel for very large homes in frigid areas. Conversely, in a tropical climate or warm southern state, even a mid-range tankless can perform very well – which is why brands like Marey and Marey (originating in warm regions) have been popular there. Also consider altitude: Navien and Noritz auto-adjust for altitude on some models, which is a plus if you live in high elevation (over ~6000 ft) where thinner air can affect combustion.
• Usage Scenario: Are you equipping a full-time residence or a weekend cabin? For a full-time family home, durability and support matter – Rinnai, Rheem, Navien, Noritz, Stiebel all have strong track records here. For a cabin, workshop, or mobile home, a smaller unit from Takagi, Marey, or Eccotemp/Camplux might suffice and save money, since it won’t be used as intensively. If you want something for camping/RV specifically, Camplux and Eccotemp portable units are tailor-made for that.
• Brand Support and Service: If you value having a technician who knows the brand or easy warranty service, consider the brand’s presence in your area. Rinnai, Rheem, Navien typically have authorized installers and service techs in most cities. Stiebel Eltron has good phone support and a growing service network (plus electric is simpler to service in general). EcoSmart and Marey might require you or your plumber to do simple part swaps (with parts they send under warranty). Check if local plumbing companies have experience with the brand you choose – this can make maintenance down the line smoother.
• Energy Efficiency and Eco Goals: If your goal is maximum energy savings and eco-friendliness, look at condensing gas units (Navien, some Rinnai/Rheem/Bosch models) which waste less heat, or at electric units powered by renewable energy (Stiebel or Rheem/EcoSmart with solar or green grid power). While all tankless are more efficient than standard tanks, the differences add up if you’re aiming for a green home. Also, consider low-flow fixtures in tandem with tankless to reduce demand – brands like Stiebel Eltron actively manage flow to save energy, which aligns with eco-conscious living.
• Warranty and Peace of Mind: If you want long-term peace of mind, pay attention to warranties: Rinnai, Noritz, Navien, Stiebel provide solid coverage (10-15 years on heat exchangers). EcoSmart’s lifetime warranty is great on paper if you follow the rules. Rheem’s accessible warranty service might appeal to some. If you’re the type who doesn’t mind tinkering, a shorter warranty might not bother you – but if you want the company to stand behind the product for a long time, lean to those with robust warranty terms.
Encourage Further Research – Model-Specific Reviews: Once you narrow down a brand or two, we highly recommend checking out our individual product reviews on ReviewHot for specific models. In those reviews, we list detailed pros and cons of each model, performance observations, and user feedback after real-world use. For example, if you’re eyeing a Rinnai unit, read our review of the Rinnai V53DeP or Rinnai RUCS series; if considering EcoSmart, see our breakdown of the EcoSmart ECO 27, etc. These will give you a feel for each heater’s quirks and advantages beyond the general brand reputation. They often answer practical questions like how loud a unit is, how well it handles simultaneous showers, or tips for installation that others found helpful.
Conclusion: The tankless water heater market has a brand and model for virtually every scenario – from high-tech, high-capacity units that can run a big household, to tiny heaters that mount on a fence and give you a hot camp shower. Major brands like Rinnai, Navien, Noritz, Takagi, Rheem, Bosch, Stiebel Eltron represent the pinnacle of performance, durability, and advanced features – they’re great for ensuring whole-home comfort and long-term reliability, especially when installed by professionals. On the other hand, EcoSmart, Eccotemp, Camplux, Marey open the doors for many to enjoy tankless benefits at a lower cost or in unique situations (off-grid, portable needs).
When comparing, keep in mind your specific needs and constraints – there isn’t a one-size-fits-all answer, but there is likely a perfect fit for you. By considering the factors above and consulting detailed reviews, you’ll be well on your way to choosing a tankless water heater that will provide you with efficient, endless hot water for years to come.
Final Tip: Once you have your tankless water heater up and running, don’t forget about maintenance. Descaling (flushing the unit with a vinegar solution or a de-scaler pump kit) once a year (or as recommended, especially in areas with hard water) will keep any brand of tankless performing at its best and prolong its life. Also, cleaning any inlet filter screens quarterly can prevent flow issues. Taking care of your new tankless heater ensures you fully reap the benefits of its energy efficiency and longevity – making your investment in a quality brand even more worthwhile.