Best Electric Tankless Water Heater

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Best Electric Tankless Water Heater

Are you fed up with all the hustle and bustle that comes with using your old conventional water heater? Well, we’ve got a solution for you. On demand electric water heater!

Unlike regular Tank Style Water Heaters, Electric tankless water heaters take up less space, heat water faster, and are generally more convenient to use.

Electric water heaters heat water on-demand, thus saving the huge energy costs of keeping an entire tank heated up 24/7. They heat water as it passes through the pipes, thus eliminating the need for a water storage tank.

Although electric water heaters are standard and readily available in most hardware and appliance stores, choosing the best one can be daunting. You have to select from among many choices, most of which are advertised as the best one, making it even harder to distinguish the fakes from the real deal.

We spent more than 20 hours researching and reviewing many On Demand Electric Water Heaters, leveraging buyer reviews and expert opinion to create a list of the seven Best Electric Tankless Water Heaters. From those seven products we found Stiebel Eltron 36 Plus Tempra to be the Best Electric Tankless Water Heater overall.

We’ve prepared a review of some of the best electric tankless water heaters on the market. We’ll also tell you everything you ought to comprehend before you go shopping for one.

Best Electric Tankless Water Heaters

  1. Stiebel Eltron 36 Plus Tempra Electric Tankless Water Heater – Best Overall
  2. Bosch Tronic 6000C WH27 – Best for Convenience
  3. EcoSmart ECO 27 – Best for budget
  4. Rheem RTEX-27 – Best for power
  5. Sio Green IR260 POU Infrared – Best for small homes and RVs
  6. iHeat Electric Tankless Water Heater – Best for small commercial properties
  7. Eemax EEM24018 Electric Tankless Water Heater – Best for quality and affordability

Best Electric Tankless Water Heater Reviews

1. Stiebel Eltron 36 Plus Tempra Tankless Water Heater

From vehicles to electronic appliances, Germany has been known to produce some of the highest quality products available on the market, and they didn’t disappoint us with this one. The Tempra 36 Plus has an innovative design and impressive build quality.

With this electric water heater, you can say goodbye to needless energy costs. This is because it automatically adjusts its internal settings to use as little power as possible while delivering optimum results.

When you’re using a lot of water, it automatically reduces water pressure. This ensures that the water gets heated up to the right temperature before it gets to your faucet.

Stiebel Electirc Tankless Water Heater

This ensures that you don’t have to deal with uncomfortable water fluctuations when another water outlet is turned on.

It also makes it ideal for high-usage applications where you don’t want to ration your hot water usage.

On the downside, it has a pretty high price tag, but considering its suitability for use in high-demand residential settings, it’s a very good option.


  • Warranty – 3 year Limited
  • Suitable for – large households
  • Water temp – 86 to 140 degrees Fahrenheit
  • Flow rate – 3.9 to 7.5 GPM
  • Installation type – Internal


  • Automatic water pressure adjustment
  • High-quality and durable construction
  • Three-year warranty on all parts
  • Easy to use
  • Silent operation


  • Quite expensive

2. Bosch Tronic 6000C WH27 Electric Tankless Water Heater

Bosch is among the most reputable brands when it comes to home appliances. If you need an electric water heater that will serve your entire household with hot water efficiently, without taking up much of your space, then you’d better check out the Bosch Tronic 6000C WH27.

This electric water heater features a simple, user-friendly user interface that requires no prior experience to operate. In terms of efficiency, you will appreciate the fact that this tankless water heater is designed to replace a 40-gallon tank heater. 

So, unless you’ve got dozens of people living in your household, this heater will provide enough hot water for a medium household.

Bosch Electric Tankless Water Heater

One of the most impressive attributes of this electric heater is its durability, apart from its good looks. It comes fitted with two solid copper heat exchangers and brass fittings for optimum durability.

It also features a thermal cut-out switch that helps you save on power and protects the heating elements from overheating damage. 

When it comes to installation, it doesn’t get any easier than this. The Bosch Tronic 6000C WH27 comes with all necessary installation gear, and its sleek design enables it to be fitted anywhere around the house.


  • Warranty – 5 year Limited on Heating Module, 2 Year Limited parts and components
  • Suitable for – Medium households
  • Water temp – 95 to 135 degrees Fahrenheit
  • Flow rate – 0.8 GPM
  • Installation type – Internal


  • Sleek, modern design
  • It can easily be installed in tight spaces
  • It has a built-in flow sensor
  • It has a durable construction


  • Has a higher activation flow than most units

3. EcoSmart ECO 27 Electric Tankless Water Heater

If you are looking for the best electric tankless water heater that will offer you all the benefits of a high-end model at a fraction of the price, then this might be the heater for you.

The EcoSmart ECO 27 comes equipped with self-modulating technology. This allows it to adjust the amount of energy used to balance the amount of water needed for optimum energy-saving and efficiency.

Like our previous pick, this water heater also comes equipped with automatic thermal protection that protects the unit from damage and cuts down on power wastage.

EcoSmart ECO 27 Electric Tankless Water Heater

Among its most impressive features is the intuitive digital interface that can deliver one degree’s temperature increments during adjustment. It can also achieve 3.48 GPM when the incoming water temperature is 52 degrees. Impressive, right?

Despite its affordable price, the EcoSmart ECO 27 has an impressive build quality, and it also looks pretty good.


  • Warranty – Lifetime Limited
  • Suitable for – Small to medium households
  • Water temp – 80 to 140 degrees Fahrenheit
  • Flow rate – 0.3 GPM
  • Installation type – Internal


  • It enables you to adjust the water temperature in one-degree increments.
  • Made of copper and stainless steel components
  • It is pocket-friendly.
  • It comes equipped with auto thermal protection


  • Must be installed professionally within 30 days of purchase. If you don’t install it within the set period, you will not be eligible for the limited lifetime warranty

4. Rheem RTEX-27 Electric Tankless Water Heater

It’s no wonder the Rheem RTEX-27 made it to our list because it’s from one of the most reputable brands in the market.

This electric water heater features a very user-friendly design and a minimalistic appearance that enables it to fit and blend in any part of your house.

In terms of performance, the Rheem RTEX-27 can deliver 6.6 GPM, which is enough to service up to four showers and one faucet simultaneously, making it suitable for small to medium homes.

Rheem RTEX-27 Electric Tankless Water Heater

This electric heater features an easy-to-use analog electronic temperature control with an easy-to-read display. The control unit can make temperature adjustments in one-degree increments, making it very convenient.

It also comes equipped with advanced self-modulation technology that allows it to meet all your hot water demands while saving on power. It achieves this by adjusting the amount of energy used to meet the amount of water required.

This electric tankless water heater is built to last. It comes equipped with three copper immersion heating elements with brass tops. These heating elements not only last longer but are also serviceable.

With this heating unit, you can expect it to deliver an impressive 4.0 GPM at a 46 degrees Fahrenheit temperature rise.

Fahrenheit temperature rise.


  • Warranty – 5 Year Limited
  • Suitable for – Small to medium households
  • Water temp – 80 to 140 degrees Fahrenheit
  • Flow rate – 6.6 GPM
  • Installation type – Internal


  • The heating elements can be serviced in the field.
  • It is very powerful, i.e., it can deliver a maximum GPM of 6.6
  • It is fitted with advanced self-modulation technology


  • Quite expensive
  • Professional installation is recommended

5. Sio Green IR260 POU Infrared Electric Tankless Water Heater

If you are looking for the best electric tankless water heater for your small home or RV, then this might be the best water heating system for you. 

One of the first things you’ll notice when you take a look at this heater is its high-tech looks, which makes it very visually appealing, not to mention the fact that it can blend in with any house or RV indoor décor.

The Sio Green tankless water heater is made entirely of non-metallic materials, making it particularly suitable for hard water areas.

Unlike most electric water heaters out there, the non-metallic materials on this heater are not affected by limescale.

Sio Green IR260 Electric Tankless Water Heater

This means that apart from being super convenient and energy-saving, this unit requires little to no maintenance.

On the downside, the Sio Green IR260 only offers 50 degrees Fahrenheit temperature rise, which means that it cannot perform well with very high flow rates.

That being said, the infrared technology it runs on is a relatively new concept in water heating, so we can expect to see improvements in later models.


  • Warranty – 2 Year Warranty, and a 30-day money-back guarantee
  • Suitable for – Small households
  • Water temp – 77 to 140 degrees Fahrenheit
  • Flow rate – 0.8 to 1.5 GPM
  • Installation type – Internal


  • Made of non-metallic materials; hence requires no maintenance
  • Elegant high-tech design
  • 99% energy efficient
  • It has a compact design


  • Quite expensive
  • Not as powerful as similarly-sized models

6. iHeat S-12 Electric Tankless Water Heater

With the iHeat Tankless heater, you can finally enjoy an unlimited and uninterrupted hot water supply on your small property.

This compact, wall-mounted unit is made of stainless steel, which makes it very durable. It’s reasonably lightweight. Its compact design makes it an easy fit for most small homes, commercial settings, and even yachts.

It features a waterproof interactive touchpad that enables you to make easy temperature adjustments and other controls.

It comes with a default temperature setting of 32 degrees, but it can go as high as 105 degrees Fahrenheit.

iHeat S-12 Electric Tankless Water Heater

On the downside, the 2GPM it offers is considerably lower than most products on our list, but considering the energy efficiency that comes with it, I’d say it’s a pretty good take.

Weighing only 8 pounds and with a compact design, this electric tankless water heater is very easy to install. It also comes loaded with various safety features that make it very safe to use.


  • Warranty – 3-year limited warranty for components, 1-year warranty for heating elements, and 5 year warranty for leaks.
  • Suitable for – Small households and commercial settings
  • Water temp – 32 to 105 degrees Fahrenheit
  • Flow rate – 2 GPM
  • Installation type – Internal


  • The warranty covers all components and leakage
  • The water heater is energy efficient
  • It has a durable stainless steel construction
  • It has a waterproof interactive touchpad that makes it very easy to use


  • The low GPM makes it unsuitable for use in large homes
  • Not very durable

7. Eemax EEM24018 Electric Tankless Water Heater

If you are looking for an affordable electric tankless water heater that will give you all the convenience and energy-efficiency of a high-end model without sacrificing quality then this is the unit for you.

This electric tankless water heater features a stylish design that enables it to fit perfectly into any décor.

Its compact and lightweight construction also makes it easy to install, although professional installation is still recommended.

It comes loaded with lots of safety and energy-saving features, including a self-modulating technology that helps you save energy by relating your energy output as per your needs.

If you don’t have many showers or faucets in your home, then you will appreciate the 3.5 GPM and a temperature range that goes as high as 140 degrees Fahrenheit.

Eemax Electric Tankless Water Heater

It also features an easy-to-use digital temperature control system that enables you to make temperature adjustments in one-degree increments, giving you more control.


  • Warranty – Five-year warranty for leaks, one-year warranty for parts
  • Suitable for – Small to medium households
  • Water temp – 80 to 140 degrees Fahrenheit
  • Flow rate – Max 7 GPM
  • Installation type – Internal


  • It has a flow rate of 3.5 GPM
  • Easily adjustable temperature control
  • Highly energy-efficient
  • It is easy to install


  • Not suitable for whole-house use
  • It has a slight delay before it reaches its activation point.

Factors to Consider when Buying an Electric tankless water heater

1. Size

Before you head out to buy an electric tankless water heater, ensure that you measure the amount of space you’re willing to spare for your new heating system. Unlike tank units, tankless water heaters don’t have a buffer to fall back on.

This means that if you select a smaller heater than you need, then the water delivered to your showers and faucets might not be warm enough.

However, if you plan on installing your unit indoors, you should go for a compact model since they take up less space and are more aesthetically-pleasing.

That being said, it is essential to note that to size your electric tankless water heater correctly, you need to determine your desired flow rate and temperature rise (we will elaborate further on this subject below)

2. Energy efficiency

Although tankless water heaters outperform tank water heaters in energy efficiency, their efficiency levels differ from model to model. The more energy efficient a tankless water heater is, the less costly it is to run.

When determining the energy efficiency of a tankless water heater, you need to consider its energy rating. Energy rating is determined by dividing the energy input required by the heater and its energy output.

3. Temperature rise

Temperature rise can be defined as the difference between groundwater temperature and your desired output temperature. To determine temperature rise, all you have to do is subtract the groundwater temperature in your area from your desired output temperature. 

It would be best to buy a tankless water heater that will offer a temperature rise of at least 100 to 115 degrees Fahrenheit.

4. Price

Your budget is probably an essential factor to consider when shopping for an on-demand electric tankless water heater. After all, you can’t buy anything that’s above your budget, right?

Having your budget in mind will enable you to cross out the units that don’t fit your budget. This will leave you with fewer choices to choose from, which might help you make a better choice.

That being said, like any other product out there, the price of an electric tankless water heater is determined by its quality, efficiency, durability, and other factors. This means that high-quality heaters are generally more expensive than their ‘low-quality- counterparts.

If you are on a budget, you can sacrifice features like touchpad control panels and other luxury features and still end up with a high-quality heater that will serve you well as a high-end model.

5. Warranty

Warranties vary from model to model and from manufacturer to manufacturer. Many manufacturers out there require you to register your electric tankless water heater within a particular duration after purchase. They also require you to have it professionally installed to be eligible for warranty coverage.

The duration of a tankless water heater’s warranty says a lot about its quality. This is because manufacturers are more likely to stand behind a product they believe in with lengthy warranties instead of one they don’t believe in.

Many warranties fall within the following ranges:

  • Parts: 2 to 5 years
  • Heating element: 3 to 10 years
  • Leakage: 5 to 10 years

6. Flow rate

Flow rate is the amount of water that will be flowing through your electric tankless water heater at any given time. To calculate the most appropriate flow rate for your new heater, you will first need to determine the maximum number of hot water devices you can use in your house at any given time. This is referred to as peak hour flow rate.

To determine your peak hour flow rate, all you have to do is add up the GPM (gallons per minute) of each device in your house, i.e., showers, faucets, washing machines, and dishwashers.

You can use the following guideline:

  • Kitchen faucet: Older faucets 3 to 7 GPM/ 1992 standard 2.2 GPM
  • Shower: Older shower heads 4 to 8 GPM/ 1992 standard 2.2 GPM
  • Bathroom faucet: Older faucets 3 to 5 GPM/ 1992 standard 2.2 GPM

For example, if you plan on running one kitchen faucet, two showers, and one bathroom faucet during your peak hour, then your peak hour flow rate is:

[(3+ (2 X 2.2) +2.2] = 9.6

7. Installation type (inside the home, outside, or point of use)

If you are replacing a conventional water heating system, then the best place to install your new system is where the conventional unit was. This is because all the piping is already in place, so you don’t have to incur extra labor and material costs.

Most electric tankless water heater units are waterproof and can therefore be installed either inside or outside. That being said, you must contact your manufacturer or look for installation guidelines in your user manual.

If you intend to supply only a few appliances with hot water, you can consider installing the unit at the point of use. Installing the unit closeby will ensure that you get hot water faster. It also reduces the amount of heat energy lost by water as it travels from the heater to the faucet.

That being said, your home’s electric and pipe configurations can also affect where you place your electric tankless water heater.


Installing an electric tankless water heater in your home is not only cheaper but also more convenient than using a conventional water heater. Although electric units are more costly to install than their traditional counterparts, you will enjoy substantial energy-saving benefits in the long run. 

All the heaters on our list are the best in their category and are guaranteed to give you quality service. 

Before you go shopping for a new electric tankless water heater, remember to read through the factors discussed in the buying guide section. Doing that will ensure that you end up with a high-quality model that will serve its intended use perfectly.

Visit your preferred store and shop. All the best out there.


What is the most significant benefit of an electric water heater?

Affordability is one of the top benefits of an electric water heater. The cost will vary depending on the size and type of water heater. Unlike gas water heaters, electric water heaters do not require a ventilation system, making installation quick and straightforward.

What is the most significant benefit of a tankless water heater?

One of the most significant advantages of tankless waters eliminates the extra cost of holding 40-50 gallons of hot water in a storage tank. It also offers a continuous supply of hot water.

The H2Home Lab team is dedicated to helping you find the best solutions to your specific water needs, as well as provide troubleshooting tips and guides for water filtration, heating, softening and plumbing. We hope you will find the info you need on our site from any one of our buying guides or subject matter articles.