Reviews of The Best Electric Tankless Water Heaters of 2019

Published by Alexa Bartel on

Reviews of The Best Electric Tankless Water Heaters of 2019

Many people are making the switch from a traditional hot water tank to a point of use or on-demand electric tankless water heater — and for good reason.

There are several benefits to using these systems in your home including monthly electricity savings, cheaper up-front costs and easy installation.

In general, these products are used as point of use solutions under a sink or for single appliance use. When you are looking for the best electric tankless water heater for your home, it’s easy to be intimidated by the many different models on the market.

Every home and homeowner is different, which is why we’ve put together a comprehensive buying guide with tankless water heaters reviews to help you identify the right make and model for your needs.

  • The most powerful water heater in the market
  • Advanced flow control for enhanced savings
  • Compact design fits almost anywhere
  • Advanced flow control for enhanced savings
  • Compact design fits almost anywhere
  • Runs 100% silent with no mechanical switches
  • Industry leading brand in hot water heaters
  • One of the best warranties in the business
  • Adequate flow rate at 3.0 – 3.5 GPM
  • Non-Metallic material requires no maintenance
  • Beautifully designed
  • Environmentally free
  • A lot of power in a small package
  • Backed by industry leading brand
  • Great for cabins and cottages
  • Highly energy efficient (save 50%)
  • Adjustable LED Display Temperature Controls
  • Great safety features
  • Durable Stainless Steel design
  • Energy-efficient Temperature Adjustment
  • 1, 3. 5 yr Warranty
  • Easy to install
  • Adequate 3.5GPM Flow Rate
  • Economically priced
  • Smart-enabled Temperature Control
  • Great for 2-bathroom household
  • 5 yr warranty

9 Best Electric Tankless Water Heaters Reviews of 2019

Stiebel Eltron’s flagship product, the Tempra Plus, is one of the best electric tankless water heater models on the market. With one of the highest GPM flow rates available at 4.0 GPM and the ability to raise the temperature 50F, this model provides the best performance you can expect from this type of heating system.

We love that even though this tankless electric water heater is the most powerful you can find, it is not much more expensive than a unit half its size. This makes the model all the worthwhile when paired with its modulating power technology and advanced flow control.

The Tempra Plus is one of the only one of its kind to also have advanced flow control. You can limit the amount of flow when hot water is not required, resulting in even more energy savings. Think of it as Eco Mode.

For more information on advanced flow control, have a look at this short video:

While this unit is the most powerful you will find in electric tankless, it is not powerful enough to provide hot water to an entire home. We would recommend installing a unit in each room that requires hot water. It is powerful enough to run a shower and a bathroom sink; a washing machine and laundry sink or a dishwasher and a kitchen sink.


  • The most powerful water heater in the market
  • Advanced flow control for enhanced savings
  • Compact design fits almost anywhere
  • Runs 100% silent with no mechanical switches


  • Slightly more expensive than heaters
  • Design isn’t elegant; you’ll want to hide the unit

The bottom line: If you want the best electric tankless water heater available, and don’t mind spending a few extra bucks, this is the unit for you.

Read the full in-depth review: Stiebel Eltron Tempra Plus 36 kW.

The EcoSmart ECO ranks second on our list of tankless electric water heater reviews. The model (Eco 36) boasts one of the best GPM flow rates available at an impressive 3.5 GPM with a temperature rise of 40F. It may not be as powerful as the Tempra Plus, but this instantaneous electric water heater is generally sufficient to supply an entire room, such as a kitchen, bathroom or laundry room.

If you are looking to power your entire house with an EcoSmart ECO 11 installation, you will need to purchase several units – ideally one for each room.

As you’ll see with the rest of the items on our list, both the EcoSmart ECO and the Tempra Plus are in their own class. Their performance is roughly similar and sufficient for any’s room needs. When it comes to design, the EcoSmart isa clear winner, If you need to place this in a laundry room, it will have an elegant and modern feel even if it is exposed.


  • The most powerful model on the market
  • Advanced flow control for enhanced savings
  • Compact design fits almost anywhere
  • Runs 100% silent with no mechanical switches


  • Slightly more expensive than others
  • Design isn’t elegant; you’ll want to hide the unit

 The bottom line: If you want the best electric tankless water heater available, and don’t mind spending a few extra bucks, this is the unit for you.

Read the full in-depth review: Ecosmart ECO 36 36kw 240V.

Rheem’s top model, the Rheem RTEX-18, offers some of the best value. In addition to the peace of mind you get when buying from a company that has been around for decades, you get most of the features available from premium models at a lower price. The premium brands usually cost more, but with this model, you can get the big brand for less.

Rheem claims that this unit is a 4 gpm system, but real-world tests with cold incoming water, reflected in rheem tankless water heater reviews, have found that 3.0 – 3.5 GPM is more reasonable to expect. Of course, 3.5 GPM is a sufficient flow rate to power the needs of almost any room in the house.

The challenge with this is that it may take up too much space under a sink. In addition, it isn’t the most visually appealing unit either. But these might not be factors for you, if you have lots of hidden space to place the unit.


  •  From the best electric water heater brand
  • One of the best warranties in the business
  • Adequate flow rate at 3.0 – 3.5 GPM
  • 99.6% energy efficiency
  • Great price


  • Larger than most units, not suitable for small spaces
  • Does make some noise, although it’s not loud

The bottom line: If you want good value and a good brand for an affordable price, this unit is for you.

If you live in an area with particularly hard water, or you are looking for a heating system for an RV or tiny home, you should consider the SioGreen IR260.

This model was made with non-metallic materials, meaning that limescale doesn’t build up in the unit. Thanks to this innovative technology, this is one of the only heating products on the market that doesn’t require any maintenance.

Of course, this tremendous advantage is not without its downside. The SioGreen IR8000 isn’t capable of very high flow rates at a 50F temperature rise. It is definitely best suited in late spring to early autumn or in warm climates that don’t require a high-temperature rise.

Infrared technology in these systems is a relatively new technology and we expect to see improvements over the coming years. After all, the maintenance aspect of going tankless can be a challenge for many people.

It is also worth noting that this model is visually appealing and looks as high-tech as it is. This product is advertised as a whole house tankless water heater, but we think you’d be disappointed if you purchase a single unit for an entire house.


  • Non-Metallic material requires no maintenance
  • Beautifully designed
  • 99% energy efficient


  • Not as powerful as other units available for the same price
  • Somewhat expensive for the value

The bottom line: If you don’t want to bother with annual maintenance and don’t require a lot of power, this unit is for you.

Read the full in-depth review:  Rheem RTEX 18

Rounding out our list of electric water heater reviews is this Bosch model – a compact, highly efficient unit that uses very little energy and it is backed by a premium brand.

This could be exactly what you need if you have very modest heating needs. If you are looking for a simple unit to install in your summertime cabin or cottage for a small bathroom, this is the best small electric water heater. For less than $200, you can enjoy hot water just like at home!

If you are looking for the best electric hot water heater for whole house needs, however, this may not be the system for you.
That said, this model can also be suitable for providing hot water to a sink. Anything more than that and this will prove to be insufficient. That said, there is no need to spend a lot of money if your needs are modest.


  • A lot of power in a small package
  • Backed by one of the best tankless water heater brands
  • Great for cabins and cottages


  • Not powerful enough for cold incoming water temperatures
  • A little louder than we’d prefer

The bottom line: If you want a small, simple and affordable unit for the summertime, this is the perfect unit for you.

Read the full in-depth review: Bosch Electric Tankless Water Heater.

Key Features:

  • Product Dimensions: 19 x 14.5 x 5.5 inches
  • Weight: 14.6 lbs
  • GPM: 3
  • Temperature Range: 86-125F
  • Electricity Leakage Protection
  • LED Temperature Control Display
  • Scalding Protection
  • Over-pressure and overheating Protection
  • ETL listed
  • NSF Certified

Best Suited For: Kitchen, bathroom, Cabin, Studio, 1 bedroom apartment

Description: AB WiseWater’s model isn’t premium grade, but makes our list of best electric water heater reviews because it works well enough to provide unlimited hot water when you need it.

The temperature range on this wall-mounted unit reaches a peak of 125F, which may not be as hot as you’d like for a shower or even a cup of coffee. It’s economically priced, however, and fairly easy to install.

Properly installed, this model is energy efficient and can save you up to 50% on your energy bill. 3 GPM is high enough to provide a steady flow of hot (or warm) water even while other devices are being used. You’ll be able to enjoy a hot shower on demand without waiting for your tank to replenish.

Install and use this model at the point of use (bathroom, kitchen, etc) and you’ll have the supply you need for years to come.


  • Economical
  • Energy efficient (save 50% on energy)
  • Compact size requires little space


  • Low GPM
  • Cannot be installed for outdoor use
  • Heats to a warm 125 degrees F but not hot
  • No warranty information

Key Features:

  • Product Dimensions: 3.5 x 7.7 x 11.5 inches
  • Weight: 7.5 lbs
  • 2 GPM Maximum
  • Temperature Range: 32 degrees F – 105 degrees F
  • Waterproof interactive touchpad
  • Up to 60% Energy Savings
  • Warranty: 1 yr Elements limited 3-Year Components 5-yr leaks

Best Suited For: Beachfront properties, Cabin Resort, Kitchen, Bathroom, Hospital, Commercial property

Description: With this model, you can finally enjoy back-to-back hot showers in your busy household. If you need a system for your beachfront property, bathroom, kitchen, or even your yacht, the iHeat Stainless Steel is a dream come true.

The iHeat model is a compact wall-mounted unit made of durable stainless steel. While it’s lightweight, compact and pretty easy to install, you may require copper piping and adapters to install it.

Once installed at the point of use (ie your kitchen sink, shower, etc) the iHeat provides unlimited hot water on demand, to a peak of 105 degrees C. You can control the temperature setting, beginning at the default setting of 32 degrees.

Admittedly the 2GPM is lower than many of the products in our review, but you’ll still enjoy an on-demand supply with this product. Its energy-efficient design can also save you up to 60% on your energy bill.

The best part about the iHeat is that it can be installed and used for any number of applications. As we mentioned, it’s small and weighs only 8 lbs. The waterproof touchpad prevents shorting out, among other safety features, and the iHeat is covered by generous warranties for the element, components and against leaks.

Some users warn that this unit may stop working effectively after 6 – 12 months of use.


  • Durable Stainless Steel construction
  • Energy efficient (save up to 60%)
  • Warranty includes heating element, components and leakage


  • Low GPM not suited for whole house application
  • May malfunction after 6 – 12 months

Key Features:

  • Product Dimensions:17 x 14 x 3.8 inches
  • Weight: 14.5 lbs
  • 3.5 GPM Max
  • Temperature range:  80°F to 140°F
  • 5 yr Warranty for leaks, 1 yr for parts

Best Suited For: Kitchen, Bathroom, Studio, 1 bathroom apartment or home, Office

Description: Enjoy a limitless stream of hot water on demand in your home with this stylish, sophisticated product!

The Eemax EEM24018 is a step up from some of the more economical systems on the market. What really makes it unique is the self-modulating technology, which regulates energy output based on our need.

information on water heaters best requirements like amps pole & breaker

This highly energy-efficient unit also has a higher temperature range that reaches a peak of 140F. You can adjust the temperature in increments of 1 degree, which gives you even more control.

Economical, stylish and energy-efficient, the EEMAX is an incredible bargain that delivers unlimited hot water once it reaches the activation point. You might want to purchase more than one because it works so well!


  • Adequate 3.5 GPM
  • Adjustable temperature control
  • Easy to install
  • Highly energy-efficient


  • Not designed for whole house use
  • Slight delay before unit reaches activation point

Key Features:

  • Product Dimensions:8.7 x 3.5 x 14.2 inches
  • Weight: 10.1 lbs
  • 2.5 GPM
  • ETL approved
  • Smart Control LCD Panel Display
  • 5 yr Warranty

Best Suited For: 1 -2 Bathroom Household


The Marey ECO150 is a premium quality, energy-efficient tankless water heater for 2 bathroom house living condition. Compact, and lightweight, you can install it at the point of use and it will work almost instantly. The activation mechanism can produce hot water even when the pressure and flow rate is as low as 5gpm/5Psi.

Because of its smart control technology, you can easily adjust the heater’s temperature and optimize your energy use. The LED Display gives you control of the temperature, along with safety features to prevent scalding or overheating.

diagram of Marey ECO Tankless Water Heater with Smart Technology

Some users have experienced water leakage from the back of the unit. It also requires a 1 x 70 amp double pole breaker to work effectively. Luckily, there is a 5 year warranty included. with your purchase.

Powerful enough to work on up to points of use simultaneously, this tankless electric hot water system is an affordable model. You’ll have hot water on demand for your whole family at a price you can afford!


  • Smart Technology Temperature Control
  • Energy efficient
  • 5 yr warranty
  • Economical


  • May experience leakage from the back of the unit
buying bosch product online on amazon

Buying Guide

We understand that there are many electric tankless water heaters for sale on the market, which is why we’ve put together a buying guide.

Use our guide to make identifying the best tankless water heater for your home easier. Our tankless water heater ratings are based on the different unique needs a homeowner may have.

What are Tankless Electric Water Heaters?

A on-demand water heater is a system that heats your water directly without using a storage tank [1]. The way this works is that when the hot tap is turned on, the cold water travels through a pipe into the unit, and the electrical element heats it. 

When you choose this type of system, you can rest assure you will have a continuous supply of hot water to showers, dishwashers and washing machines.

We love that these systems don’t produce standby energy losses, as opposed to traditional storage heaters. This saves you lots of money in the long run. After all, water heating accounts for 9.5 percent of a home’s electricity consumption [2].

The Benefits:

There are a wide array of benefits to investing in an inline electric water heater. Tankless hot water heaters save space, money and more. Consider the positive changes these systems can provide:

● More affordable to install
These systems are a lot cheaper and easier to install than a gas tankless hot water heater as gas systems come with the costs of venting systems and additional gas lines [3].

● Versatile installation
You can install these tankless heaters outdoors and indoors! Really wherever the system will be of most use to you. You are not limited to installation in particular areas. If you are looking to install one outdoors in a colder climate, you can use an anti-freeze kit [4].

Additional storage space
Because electric tankless water heaters are tank-free, they take up a lot less space than a traditional model. It is compact so it can fit in smaller spaces and help you save room in your home.

Doesn’t produce greenhouse gases
Tankless electric water heaters don’t produce greenhouse gases like a natural gas powered system [5].

Uses less energy
Did you know that a hot water tank could easily account for almost 25% of a family of four’s energy bill? [6] That is more than the air conditioning and other appliances combined. Fortunately, these inline systems use a lot less energy than, for example, gas tankless water heaters.

● Lasts longer
Electric tankless water heaters last around 10 years longer than traditional tank systems [7].

● Lower energy bills
At the end of the day, heating water accounts for 14% to 18% of our utility bills – this is why it’s ideal to invest in a heating system like an electric on demand water heater that will help you save on electricity and costs [8].

● You’ll never run out of hot water
With electricity operated heating systems you never run out of hot water, because the system heats it, quite literally, on demand.

● Could even improve the resale value of your home
The truth of the matter is that these systems are well worth the initial investment. A Zillow home listing analysis actually found that homes with these systems sold 43 days faster than anticipated [9].

Using Your Electric Tank-Free System

These systems are ideal for a lot of situations… but, not all of them. When looking to buy electric tankless water heater systems, you should definitely keep their restrictions in mind in any of the following situations.

Where to Use Your Tankless Electric Water System

These systems may not always be needed, but there are specific situations where they are particularly useful:

A Guesthouse or Pool House

This is a compact space to begin with, so everything in these rooms needs to be the miniature version of what you would put inside your home. You probably already have a mini bar fridge, smaller furniture, and most likely a small 2-piece bathroom.

An electric heating system works magically in these spaces, as it gives you access to hot water, without having to give up the equivalent of an entire closet space for a traditional 50-60 gallon tank [10]. A small electric tankless water heater is ideal in these situations.

That said, the best model for shower needs will be a whole house electric tankless water heater.

A Cabin, Vacation Home, Lake House or Cottage

Do you have a cozy little retreat that you use over the warmer months? This could be the perfect solution, depending on the amount of family, friends, and guests you expect to stay over.

Your standard unit is perfect to keep your sinks and faucets running hot water. However, if you’re looking at showers and bathtubs, you’re going to want to explore whole house options or a point of use electric tankless water heater for shower needs. To find the right system, be sure to consider our best whole house electric tankless water heater reviews.

A lot of vacationers love these units when it comes to close up shop for the season and winterize the home. A traditional water tank takes forever to drain (to prevent freezing), whereas a tank-free heater is drained in a few seconds.

When Not to Use a Tankless Electric Water Heater

These systems are ideal for a lot of situations — but not all of them. When looking to buy electric tankless water heater systems, you should definitely keep their limitations in mind:

Back-to-Back Showers For the Whole Family

Most of the models out there are not really for shower or bathtub use. This is particularly true for a family home where multiple people will be taking a shower, often one right after another, to get ready in the morning.

Hot water is already a precious enough commodity in the morning and this is asking too much of most of these systems.

Dishwashers and Washing Machines

Next to the shower or bathtub, your dishwasher and washing machine are going to be the biggest drains on the hot water in your home.

If your dishwasher has a heating element built into it, you can likely go tankless for this kitchen. However, if that’s not the case, you could struggle to get the water warm enough and put way too much pressure on the unit.

That said, some modern front-loading washing machines are built with tankless heaters in mind so that they can operate in a good range of efficiency. However, you need to be absolutely positive that you buy the right unit. Not all modern washers are built this way, even if they’re energy-efficient and boast how little water they use.

Any time you are looking to add appliances into the mix, chances are high that you need a whole house mode.

Solar-Powered Homes

Just to be clear about exactly what we’re talking about here, there are solar water heaters available on the market today and they certainly have their place. But, right now, we’re talking about trying to use electric tankless water heaters in a solar-powered home.

If you have (or you’re building) a solar-powered home, you’re already aware of the fact that you need to be mindful of the usage and efficiency of all your appliances, and how much demand you’re putting on your home’s own little power grid.

As of right now, it’s not really possible to heat the water with a solar thermal panel, so you’ll need to look into other options.

Cold Environments and Climates

If you’re living in a colder or more northern community and pipes freezing are an issue that you have to think about every year, you need to be very careful how and when you use this system.

You especially need to think twice about keeping the unit outside or in poorly insulated poorly heated rooms.

Before Buying Your System