Top 10 Best Tankless Water Heaters (Reviews & Buyers’ Guide 2022)
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- Best Tankless Water Heater for Sale in 2022
- Best tankless water heater of 2022; awarded an Amazon’s Choice label
- Self-modulating technology helps save 60% of water heating costs
- Includes a lifetime warranty for household use
- An Amazon’s Choice label champion; has a thermal efficiency rating of 98%
- Fast recovery rates for heating water to get on-demand supply
- Easily mounted anywhere around the house
- Holds an Amazon’s Choice award; provides consistent hot water
- Saves space due to being 90% smaller than traditional ones
- Has a thermal efficiency rating of 99%
- Boasts a 4.5-star rating on Amazon with 1936 reviews
- Has a 7.5GPM hot water flow rate to produce consistent and powerful streams
- Energy-efficient—only heats water when needed
- Sleek design affords smaller space consumption
- Operates silently to produce steaming hot water
- Uses 15-20% less energy than conventional electric tank water heaters
- Features an external digital thermostatic control with LED display (-/+1 degree accuracy)
- Has self-modulation technology to provide constant hot water streams
- Flow rate can reach up to 4.4 GPM thanks to durable copper immersions
- Delivers 3.18GPM of endless hot water to ensure convenience
- Being a compact instant water heater promotes space-saving criteria
- Product comes with an oxygen-free copper heat exchanger and v-type stainless steel burner to achieve 89.98 heating efficiency
- Water heater technology brings a limitless supply of hot water
- Only heats water when needed saving up to 40% of energy in the household
- Automatically adjusts power input based on the set flow rate thanks to self-modulating technology
- Features eco and full gas switch for energy saving
- Has a force exhaust fan for comfort and safe ventilation
- Propane water heater is equipped with a safe electronic ignition system
- Has an Amazon’s choice label; considered a great investment by several customers
- Provides an endless stream of hot water for an entire household
- Possesses a self-modulating technology to adjust energy levels based on specified hot water requirements
If you’re tired of relying on a kettle, then maybe it’s time you consider tankless water heaters. Their invention has helped many American households with their daily hot water needs, particularly those living in cold areas. They’re technically considered upgrades of their predecessors that use tanks of varying sizes.
The first electric tankless water heater was invented by Stiebel Eltron in 1929. Although the earliest models showed potential, their efficiency had been wildly inconsistent and wasn’t enough to compete with standard tank water heaters. Furthermore, their competitors were massively popular at the time, making it difficult to break free from a concentrated market.
It was not until the 1990s that energy-efficient water heaters started to gain traction. Improvements in efficiency led most parts of Europe to begin purchasing more of them. Soon after, America followed suit and started to implement timely upgrades such as thermostatic controls, LED displays, and the application of self-modulating technology. Customers would eventually replace their conventional tank water heaters to avail of such amazing features.
With more and more households starting to acknowledge their development and benefits, we cannot deny that commercial tankless water heaters have revolutionized the way we fetch hot water. The immense number of advantages they offer has benefited millions of customers, and will only continue to grow with time. Thus, choosing the right fit should be strongly decided upon.
At Engineer Warehouse, we have gathered ten of the best tankless water heaters on the market. They were carefully filtered out from hundreds of eligible contenders and underwent a series of evaluations done by our resident experts. These curated selections form part of an extensive product guide that includes their own reviews, specifications, frequently asked questions, and some of the best tips on how to properly use them. With our guide in your hands, you’ll be having your choice tankless water heater in no time.
With thousands of viable options to choose from, finding the right tankless water heater can prove to be difficult. Hence, we at Engineer Warehouse spent countless hours of research to have them narrowed down into ten selections, each with its own extensive product review.
To justify the selections that made the exclusive list, our team of experts thoroughly evaluated them in accordance with the following criteria: Energy Efficiency, Flow Rate, and Cost-Efficiency.
Tankless water heaters are primarily known for their high efficiency, only discharging hot water when needed. Although their heating process requires more power, their lack of a tank means they do not have to reheat water repeatedly. As a result, they expend way less energy compared to standard tank water heaters. Evaluating their energy efficiency not only helps us rank our selections, but also determines the unit’s overall impact and performance.
For starters, flow rate is the volume of fluid (water) that passes through per unit time. It varies from model to model, depending on its specifications and design. The higher the flow rate, the faster the fluid can go through a pipe and fill the demand.
Although commercial tankless water heaters can technically discharge hot water without any limit, having a low flow rate can affect their overall performance. Thus, evaluating their flow rates can help us gauge their capacity to support a household at any given time.
This criterion directly correlates with energy efficiency. Since tankless water heaters are designed to be energy-efficient, they are expected to drastically reduce incurred energy costs.
Although the upfront fees will cost you a substantial sum, their high cost-efficiency should compensate for it over time. Evaluating their annual cost against the hot water provision will determine their cost efficiency, as well as value.
View the Best Tankless Water Heaters in the Market Below:
|Item Weight||14 Pounds|
|Dimensions (L x W x H)||3.63 x 14 x 17 Inches|
The EcoSmart ECO 18 Electric Tankless Water Heater is ranked number 1 for good reason: cost-efficiency. Acquiring an average rating of 4.5-stars on Amazon, the product has been revered as the best electric water heater by numerous customers.
An electric tankless water heater hailing from one of the best-selling manufacturers, the EcoSmart ECO 18 has an Amazon’s Choice award under its belt and has been continually racking up positive reviews.
The EcoSmart ECO 18 has an energy output of 18kW, enough to support small houses, apartments, and larger point-of-use applications. It can diffuse up to a maximum of 4.3 gallons of hot water per minute, depending on the water inlet temperature.
Its patented Self-Modulating Technology grants up to 60% water heating cost reduction—user reports say that the product drastically reduced the costs leading to powerful word-of-mouth marketing (several positive reviews are attributed to friend referrals). The technologically-advanced process allows water heaters to automatically regulate the amount of energy needed to produce a continuous stream of steaming hot water.
Positive user reviews also pointed out its compact design; the Ecosmart tankless water heater allows users to save 12 cubic feet of space since it’s 90% smaller compared to traditional water heaters. The ECO 18 can also be wall-mounted to further save floor space.
The Ecosmart tankless water heater comes with a lifetime warranty for residential use.
|Item Weight||17.3 Pounds|
|Dimensions (L x W x H)||13.75 x 13.5 x 13.75 inches|
The Bosch Electric Mini-Tank Water Heater Tronic 3000 T belongs to an exclusive group of top-tier products (Amazon’s Choice) and is easily one of the best electric water heaters on the market. This battery-powered electric water heater scored a 98% thermal efficiency, granting users decreased energy consumption whenever it starts to heat water. Reduced energy consumption ultimately leads to reduced water costs—a perfect display of German engineering.
The mini-tank water heater can hold four gallons of water at a time, but can continuously dispense hot water as needed. Reviews say that four gallons are enough to fill two kitchen sinks for a day’s use (including sanitary and waste handling). The product is guaranteed to last long, thanks to its premium glass-lined components and thick CFC-free foam insulation.
As one of the top tankless water heaters, it is equipped with a pressure relief valve for enhanced security. It protects the unit by draining water should it present spiking amounts of pressure during operation. For convenience, have the water heater mounted somewhere safe and familiar to easily configure flowrates according to preference.
The product comes with a six-year warranty and a separate two-year warranty on parts.
|Item Weight||6.5 Pounds|
|Dimensions (L x W x H)||3.75 x 8 x 11.5 inches|
Another product from EcoSmart joins the prestigious list: the EcoSmart ECO 11 Electric Tankless Water Heater. The watered-down version of the 18-kW variant is still capable of bringing continuous hot water to numerous households. Just like its successor, the ECO 11 also bears the Amazon’s Choice label.
The Ecosmart tankless water heater houses a built-in LED display to continuously monitor water flow rate and temperature. The Digital Temperature Control panel is available for tweaking the current configuration or setting the required temperature in small increments. Since it uses lower power during operation, expect to have reduced costs every month. Not all households need the bigger 18-kW water heater; the 13-kW should already suffice if you do not have large hot water consumption.
The ECO 11 utilizes an energy-efficient process called Self-Modulating Technology; the patented feature controls energy consumption during operation. It enables the electric tankless water heater to only heat the required amount of water and becomes idle once delivered.
Having the ECO 11 can service a household of four, while also taking up 90% less space than traditional water heaters. Pretty neat.
|Item Weight||45.6 Pounds|
|Dimensions (L x W x H)||17.32 x 30.51 x 12.8 Inches|
Another product suitable for consumers is the Rinnai V75iP Tankless Hot Water Heater. The gas-powered instant water heater sits comfortably at number four, with a 4.5-star rating to its name on Amazon.
The Rinnai tankless water heater has one of the highest flow rates on the list, capable of dispensing hot water at 7.5 GPM (gallons per minute). Water temperature can be properly monitored and controlled via its front panel; just manually press the buttons to adjust incoming streams.
For additional security measures, the V75iP has a proprietary Temperature Lock installed to avoid any unauthorized changes to the water temperature. That way, heating coils can sit with the current temperature and not cause any abrupt changes.
The Rinnai tankless water heater is equipped with a leak detection system. Whenever the system detects a possible leak, it automatically shuts itself down to prevent further internal damage. Also, the product comes with an enhanced scale detection to reduce the possibility of serious damage in the future. This feature manages internal heating coils and prevents them from forming limescale during continuous operation.
|Power Source||Corded Electric|
|Item Weight||16 Pounds|
|Dimensions (L x W x H)||4.63 x 16.63 x 14.5 Inches|
For uninterrupted streams of hot water, avail of the Stiebel Eltron Tempra 15 Tankless Water Heater. As one of the best instant water heaters on the market, the Tempra 15 boasts a 4.6-star rating on Amazon. User reviews are overwhelmingly positive, with one customer installing over 50 of them in different houses and not once encountering an issue.
The corded electric water heater offers output water temperatures ranging from 68° to 140°F, and its small yet sleek design helps save storage space in the house. During operation, the Tempra 15 uses 15% less energy compared to conventional electric water heaters. Less energy directly correlates with less power consumption, which in turn lessens water costs.
One thing to notice about the product is its simplicity. You can avail of the continuous streams of hot water at a press of an electronic switch. The Stiebel Eltron tankless water heater also works silently; it will not emit loud noises at any point during operation. If you wish to change the temperature, just tweak the configurations present on the digital temperature display. Easy-peasy.
Although the Stiebel Eltron tankless water heater is of superb quality, the manufacturer still offers seven-year and three-year warranties on leakage and parts, respectively. Both warranties are included when purchasing the electric water heater.
|Item Weight||14.78 Pounds|
|Dimensions (L x W x H)||18.5 x 14.5 x 3.5 Inches|
Getting the sixth spot is the Rheem RTEX-18 Electric Tankless Water Heater—the highly-rated product on Amazon enjoys a 4.5-star rating alongside positive reviews from users around the globe.
The gray Rheem tankless water heater has an advanced Self-Modulating System capable of holding bursts of hot water from dispensing and regulating it according to the user’s preference. The water heater also is easy to install and requires bottom ¾-inch NPT water connections for stable flow rates.
The RTEX-18 has durable copper immersion on each of its heating elements and is also capable of producing hot water at a rate of 4.4 gallons per minute. The front panel has an external digital thermostatic display for temperature; it allows the user to monitor the temperature inside the water heater. For adjustments, a knob just located within the front panel can be rotated to suit everyone’s preference.
The electric Rheem tankless water heater can be best viewed when positioned upright, making it better when wall-mounted.
|Item Weight||27.7 Pounds|
|Dimensions (L x W x H)||14.37 x 4.72 x 25.39 Inches|
The wall-mounted Camplux 3.18 GPM Gas Tankless Water Heater is a liquid propane-powered water heater best suited for customers leading an outdoor lifestyle. Its sleek, black tempered casing isolates the white front panel, making it easy to spot. The front panel serves as its command center—the temperature regulation control and digital indicators are on display here.
The temperature controls are backed with an anti-tampering mechanism called “Child Locking” technology. This is employed to avoid unnecessary and accidental control tampering from children (or any unauthorized person).
The Camplux tankless water heater produces hot water with temperatures ranging from 95°-149°F, and at flow rates reaching up to 3.18 gallons per minute. Buying the product also comes with a 2.36-inch steel vent pipe for efficient power ventilation. Installing the product can be easy, however, it is generally recommended to seek assistance from a professional.
During operation, the Camplux tankless water heater typically generates about 42 Watts and 0.35 Amperes making it an energy-efficient appliance. Tapping in low-power appliances is extremely useful especially when facing economic disadvantages.
The energy-efficient water heater makes use of its safe electronic ignition system to fully propel heating operation using solid-state controls. The anti-freezing protection feature prevents moisture from building up internally by automatically opening up the valves during a power outage. These cool features come with a hefty price tag, though.
|Power Source||Corded Electric|
|Item Weight||21 Pounds|
|Dimensions (L x W x H)||13.12 x 3.12 x 17 inches|
The RINKMO Electric Tankless Water Heater comes from a lineage of instant and highly efficient water heaters thus obtaining a 4.1-star rating on Amazon can be quite a mark. The tankless water heater borrows the design from previous generations and improves upon it, especially on the specifications.
The product isn’t limited to the amount of water it can hold inside (unlike the traditional water heaters); the heater automatically initiates the ignition phase giving the consumer an unlimited supply of hot water while in operation. The heater exchange only functions when hot water is needed, otherwise, it sticks to the current configuration set by the temperature sensor.
A rotating knob, just below the real-time indicator, can be used to adjust the water temperature. Please note that the temperature can be switched from Celsius to Fahrenheit, and vice versa.
The tankless water heater also utilizes Smart Modulating Technology to seamlessly adjust the power consumption based on the flow rate. With this, no excess energy is wasted since the system controls the needed output. The more energy-efficient the product is, the more it is cost-effective in the long run.
Even on idle operations, the front panel stays lit to indicate the current temperature. It will be only turned off once the water heater gets unplugged or external valves are removed.
The product is perfect for indoor installations since it is designed to latch on walls. It also doesn’t need to occupy that much space since the form factor is small.
|Item Weight||23.8 Pounds|
|Dimensions (L x W x H)||12.8 x 5.91 x 20.28 Inches|
Another Camplux product made the Top 10 Best Tankless Water Heaters of 2022. As the second product to join the exclusive club, Camplux 2.64 GPM Tankless Gas Water Heater is no stranger to rave reviews (4.1-star rating on Amazon) from customers. Many have benefited from this product, thus it is only appropriate to have it on the list.
Before enjoying the product, make sure to have a gas regulator, a ⅝’’ NPT male to 1/2 ‘’ BSP female gas connector adapter to successfully integrate it with a propane tank. Call a professional for consultation—a wrong connection could make things worse.
The propane water has an electronic ignition system installed; just seconds after adjusting the temperature, the previously lukewarm water can instantly become hot. If you decide to withdraw, turn the knob back to a stable room temperature. You can verify the current temperature by viewing the Digital Temperature display.
The product offers an endless hot water supply with a 2.4 gallon-per-minute flow rate. This is made possible by applying inventive combustion technology to continuously provide streams of hot water. With virtually no wait time, anyone could enjoy hours of free-flowing hot water.
The water heater also comes with Overheat Protection feature; it protects the device from gaining a large influx of heat quickly. The Dry Combustion Protection feature prevents the internal buildup of heat during dry temperatures.
The only drawback is that this heater can’t be used for drinking water, and is strictly limited to bathroom and kitchen uses.
|Item Weight||14.27 Pounds|
|Dimensions (L x W x H)||17 x 14 x 3.75 Inches|
Perfect for commercial and residential households, the Eemax EEM24018 Electric Tankless Water Heater is a highly recommended product with tons of features. As one of the best electric water heaters on the market, it bagged an Amazon’s Choice label and is currently enjoying a 4.4-star rating from customers.
The EEM24018 electric water heater is capable of providing an unlimited supply of hot water to consumers. Its hot water temperature typically ranges from 80° to 140°F, but if you want a particular value, you can manually configure it by rotating the knob in the front panel. The knob allows the user to modify the temperature in small increments, depending on the requirement.
This small tankless water heater has a Self-Modulating Technology that allows it to dissipate input energy based on how much hot water is needed. This in turn saves energy that can be later apportioned for another hot water session. The lower the energy consumed, the lower the cost for the water heater to operate—recycling the process makes it cost-effective over time.
Its compact size makes it ideal for small households (can be wall-mounted), and inevitably saves valuable space. Also, its simple yet stylish design appeals to many customers.
Remember: if you do want to purchase and install these types of products, consult a local professional first to ensure you meet the correct requirements and avoid further compatibility issues.
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How Long Can A Tankless Water Heater Last?
On average, tankless water heaters should last anywhere between 15 to 20 years. With proper and routine maintenance, they can potentially go beyond those numbers. Their longevity alone makes them a definite choice for practical homeowners.
Although they can stay reliable for that long, high upfront costs (the unit itself plus professional installation fees) and costly tankless water heater repairs can hinder some homeowners from purchasing them.
What Are The Benefits Of Having A Tankless Water Heater?
As one of the most efficient appliances in many American households, tankless water heaters offer several excellent benefits to interested buyers.
Tankless water heaters can instantly provide a continuous stream of hot water. Their innovative design enables them to draw water from a local source and quickly raise its temperature upon demand. Since they aren’t restricted to the amount of water a tank can hold, customers are granted a seemingly unlimited supply of hot water.
The design also grants them a high energy efficiency. Since they do not need to reheat tanks to diffuse hot water, it allows them to save up to 40% energy during operation. By reducing overall energy consumption, customers can get lower monthly electric bills. The longer they use tankless water heaters, the greater their accumulated savings over time.
Also, operating without a tank also guarantees incoming water is always fresh and clean. Tanks are very much prone to rust and scale, both of which are capable of contaminating the water. By skipping past tanks, the water can’t run into them as they undergo the heating process. Hence, every time you turn on the tap, only fresh, clean water comes out, readily available for almost anything.
Unlike their standard counterparts, tankless water heaters aren’t susceptible to tank failure. The absence of a tank prevents them from having a sediment buildup, which primarily causes tanks to rupture and explode. Customers who have bought standard tank water heaters will have no choice but to replace the entire unit in case the tank gets destroyed.
And lastly, tankless water heaters take up less space since they heat water directly. Newer models are about the size of a small suitcase and can even attach themselves to walls. In comparison, standard tank water heaters can take up to 16 square feet of functional floor space. They will also need a specified amount of clearance approved by local plumbing codes to safely operate.
Will Purchasing One Tankless Water Heater Be Enough For An Entire Household?
Absolutely yes. Getting a single tankless water heater should already suffice, provided it has the necessary flow rate to deliver the daily volume of hot water needed.
If you think a single tankless water heater isn’t enough to cover most chores, then adding another should be the wisest option. You should tread carefully when exploring this option though, given the premium cost it takes to install one.
What To Look For In Tankless Water Heaters
If you’re planning to purchase a new tankless water heater or replace an older model, you may need to consider these three factors first: Energy Efficiency, Flow Rate, and Cost. They will serve as your quality guide, as there are plenty in the market to choose from.
When buying a tankless water heater, you should first consider energy efficiency. It determines the amount of hot water produced per unit of fuel (or electricity) consumed in a period and is measured as an energy factor (EF). The higher the EF, the more energy-efficient the model is.
Tankless water heaters have an energy factor ranging from 0.8 to 0.9. Experts strongly recommend getting models with at least 0.82 EF to significantly reduce heat loss and use less fuel or electricity for heating the same amount of water.
Tankless water heaters should meet the total flow rate your household requires. That way, they can comfortably support the appliances that need hot water to function, even during peak demand. It is highly recommended that your unit offers a maximum flow rate that exceeds that of the household by a mile.
To determine the total flow rate, simply add up all the individual flow rates your appliances have. The rates are usually found at the back of each one, indicated on a labeling sticker. You can also refer to the user manual in case you cannot find it.
Tankless water heaters are known to be quite expensive. They can cost anywhere between $160 to $2000; not to mention the installation fees that come with them. If you’re planning to support a small household, it’s highly recommended to prepare a large sum to cover both your unit and labor.
Hiring a professional plumber usually costs more than the unit itself, so be ready for the extra expenses. For your reference, a professional installation of top tankless water heaters starts at $1200. It may go up in price depending on how complex will the installation be.
Availing of a tankless water heater might be your best decision yet. However, just like with any other appliance, it will require routine maintenance to ensure longevity. Staying for relatively long while remaining efficient is the key to maximizing its high upfront costs.
But since deep tankless water heater maintenance is best left to professionals, you could perform some simple practices that should keep your unit running at optimal performance. Just make sure to disconnect all electrical connections prior to doing any of these practices.
Start by wiping the exterior clean using a spray cleaner and a washcloth. It may sound simple, but performing sanitation at least once a week can keep away dust and prevent rust formation.
You should regularly inspect the connecting pipes for any leaks or cracks, especially if you live someplace cold. Performing a visual inspection can prevent the freezing temperature from causing the pipes to burst open and flood the immediate location.
Make sure that the pressure relief valve stays functional. For starters, the component automatically releases water to reduce internal tank pressure if it becomes high enough. Checking its status ensures that the valve will work when needed.
If you’re done checking with the exteriors, flushing your unit should be the next logical step. Flushing regularly (every 12-18 months) eliminates any buildup of mineral deposits that can both clog the unit and cause long-term damage to internal components. An effective way of performing the process is to soak the unit in undiluted white vinegar for at least an hour. The vinegar will slowly break down the mineral deposits as it circulates, while also cleaning the interior as well.
You will need three additional things before flushing your unit: a submersible pump, a huge bucket, and a hose set. Once you have them, you may schedule the process or start right away.
The first step is to turn off any electrical power flowing through your unit. Close all the water valves and release any remaining pressure. Then, carefully attach the hoses to the cold and hot water ports, place the pump and the hot hose in the bucket and connect the cold hose to the pump. Next, pour the vinegar or any descaler available into the bucket. Open the water ports afterward, switch on the pump, and let the vinegar work its way through your unit. When it’s done, turn off the pump, close the water ports and empty the water.
If you’re not confident doing any of the above on your own, better call a local plumber for professional assistance.
Remember, as an owner, you should be responsible for taking care of your unit. Performing the above actions consistently will guarantee the longevity your unit deserves, and avoid any tankless water heater repairs.
A tankless water heater is undeniably one of the best appliances you can own. As a cost-effective option, it provides instant hot water and takes up less space in the house. Although purchasing one might be costly, the convenience it brings for the long-term is nearly unparalleled.
Features can tempt you to buy a certain model. However, you should first see to it that the model is energy efficient, has an adequate total flow rate, and totally fits your budget. Having them as your initial basis for purchasing a tankless water heater can help you decide on other factors later.
If you have finally decided on a model, ensure that your budget always covers the installation fees. That way, you can readily avail of your tankless water heater to support your household needs. Having problems with the installation will only postpone the intended start of usage, leading to inconvenience. Preparing well financially can help you start operation at the soonest time possible.
But if you’re still unsure of what to pick, do not hesitate to consult professionals. Their expertise will bring you the best recommendations and solutions to your inquiries.