7 Best Electric Tankless Water Heaters of 2023

Photo: Bosch

The electric tankless water heater is one of the most popular types of water heaters in the bathroom. Its main advantage is its convenience. It is easy to install, easy to use, and reliable.

In addition, most top-rated electric tankless water heaters come with a way that allows you to adjust the water flow as well as water temperature quickly and easily.

Above all, this is a type of water heater that does not consume a lot of space. It can be used in any type of bathroom, whether it is big or small.

If you’re looking for a way to heat water in your bathroom, then use our review and guide below to get a quality electric tankless water heater that will last you for years.

7 Best Electric Tankless Water Heaters – Review

IMAGE	​PRODUCT	​FEATURES
	1. EcoSmart ECO 11 (Small & Compact)	Competitive pricing Slim and compact form factor Very energy efficient Easy to install by absolute beginners
	2. Stiebel Eltron 36 Plus (Best for Whole House)	High power of 27 kW Modern and aesthetically pleasing Informative front display 7-year warranty on leakages
	3. Rheem RTEX-13 (Simple but Full-Featured)	99.8% energy efficiency Easy water temperature adjustment The installation process is easy
	4. Sio Green IR260 (No Maintenance Necessary)	Uses only 6 kW of power Does not require maintenance Easy to read temperature display
	5. Titan SCR2 N-120 (Slim, Compact & Efficient)	Small and compact The high flow rate of 4.0 GPM Easy to use by the whole family
	6. Rheem RTEX-18 (Accurate Temperature Control)	1° temperature adjustment accuracy The high flow rate of 4.4 GPM Digital temperature display
	7. Bosch Tronic 3000 Series (Best Space Saving)	98% energy efficiency Can be installed anywhere Silent in operation

1. EcoSmart ECO 11 – Small & Compact

Photo: EcoSmart

• Power: 13 kW, 240 V
• Flow Rate: 1.5 GPM
• Temperature Range: 80°F – 140°F
• Dimensions: 3.8 inches x 8 inches x 11.5 inches

If you do not have a lot of space in your bathroom, then the EcoSmart ECO 11 is an excellent choice to consider. Due to its small and slim compact form factor, you will have no difficulty installing it in a small bathroom.

In addition, installation is very easy with the device as all you have to do connect the 1/2-inch water inlet and outlet and make the electrical connection. That’s it. You are good to go.

This small electric tankless water heater also has a front display that shows you the water temperature at all times.

What we also like about this model is that it is quite energy efficient. Since it consumes only 13 kW of power, it will not be too expensive to run in terms of electricity cost.

Furthermore, the digital temperature adjuster allows you to adjust the temperature by increments of 1 degree, which gives you a lot of control on the temperature of your water.

This model by EcoSmart comes in different sizes and styles to suit your need. You are not limited in any way in that regard.

It is certainly one of the best models let you can find in this electric tankless water heater review, especially if you are looking for a water heater for no more than 2 people.

Pros:

• Competitive price
• Slim and compact. Does not need a lot of installation space
• Energy efficient with a power of 13 kW
• Front display shows the water temperature

Cons:

• The fairly weak flow rate of 1.5 GPM
• May take some time to heat very cold water

2. Stiebel Eltron 36 Plus – Best Whole House Electric Tankless Water Heater

Photo: Stiebel Eltron

• Power: 27 kW, 240 V
• Flow Rate: 4.5 GPM
• Temperature Range: 86°F – 140°F
• Dimensions: 4.6 inches x 16.6 inches x 14.5 inches

The Stiebel Eltron 36 Plus is definitely not a model for everybody because it is quite expensive. In fact, it is the most expensive model that you will encounter in this review.

However, if the price is not an issue, and you need the best of the best, then it is a serious model to consider.

Not only is it performing with its power of 27 kW and flow rate of 4.5 GPM, but it is also very modern looking and aesthetically pleasing.

It will immediately uplift the looks of your bathroom. Best of all, this tankless water heater comes in a wide range of sizes as well as styles to suit your need.

As with most water heaters in this category, installation is very easy, and you don’t need professional help to install it.

Furthermore, there is a wide range of adjustments that you can make with this water heater, ranging from the water flow to the temperature adjustment.

Of course, the front also has a digital display that will show you the temperature as well as the water flow at all times.

Taking the performance of 27 kW into account, we can safely recommend this model as the best whole house electric tankless water heater.

It is powerful enough to power an entire house and can be used as a heavy-duty water heater as well.

Pros:

• High performance with the power of 27 kW
• Modern and aesthetically pleasing
• Comes in a wide range of styles and sizes
• 7-year warranty on leakages and 3 years on parts

Cons:

• The most expensive tankless water heater in this review

3. Rheem RTEX-13 – Simple but Full-Featured

Photo: Rheem

• Power: 13 kW, 240 V
• Flow Rate: 3.17 GPM
• Temperature Range: 80°F – 140°F
• Dimensions: 4 inches x 9 inches x 13 inches

The Rheem RTEX-13 is a modest looking tankless water heater that focuses more and functionality rather than looks.

It has a power of 13 kW any flow rate of 3.17 GPM, which gives it an excellent performance ratio. In fact, the manufacturer claims that it is 99.8% energy efficient.

The temperature rise is pretty decent for such a small tankless water heater. As it will have no difficulty heating very cold water to any desired temperature setting.

You can easily adjust the temperature using the temperature adjuster knob right at the front of the unit. It also has a handy display that will show you the current water temperature.

When it comes to installation, no problem because this is a simple water heater that is very easy to install by anyone with no experience.

Pros:

• Small and compact
• 99.8% energy efficient
• Easy to adjust the water temperature
• Very easy to install by absolute beginners

Cons:

• Weak performance. Not for heavy-duty use

4. Sio Green IR260 – No Maintenance Necessary

Photo: Sio Green

• Power: 6 kW, 240 V
• Flow Rate: 1.5 GPM
• Dimensions: 14.3 inches x 12.8 inches x 4.4 inches

Most electric tankless water heaters on the market will require maintenance sooner or later. This is because minerals in hot water will calcify and create a deposit in the heater that requires cleaning.

This is not a problem with the Sio Green IR260 because the manufacturer has designed it in such a way that it is maintenance-free.

Furthermore, it is also quite modern looking and aesthetically pleasing, which will uplift the looks of any bathroom.

The front of the device contains many controls like the temperature adjustment, power switch, and an informative display that shows you the water temperature.

But what we like the most is its small power consumption of only 6 kW which shows that this water heater is extremely energy efficient.

Its flow rate of 1.5 GPM is pretty average but still enough to deliver an enjoyable showering experience with almost any type of showerheads.

Indeed, even if this model is definitely not the best electric tankless water heater on the market, it is very energy efficient and aesthetically pleasing.

We recommend it for anyone who does not have big water heating demands!

Pros:

• Highly energy efficient with a power of 6 kW
• Does not require maintenance
• Front display with easy temperature control adjustments

Cons:

• It can be difficult to get a warranty on this product
• Not as durable and long-lasting when compared to other models

5. Titan SCR2 N-120 – Slim, Compact & Efficient

Photo: Titan

• Power: 11.8 kW, 220 V
• Flow Rate: 4.0 GPM
• Dimensions: 12 inches x 10 inches x 5 inches

This model by Titan is made specifically for those who do not have a lot of space in their bathroom.

Indeed, it is a small electric tankless water heater that has a maximum height of only 12 inches and a width of 10 inches.

It is extremely easy to install as the inlet and outlet of threaded and easy to connect with regular plumbing connectors.

What we like about this heater is that it uses 11.8 kW of power and has a relatively high flow rate of 4.0 GPM.

This means that it will have no difficulty heating up cold water and also deliver an enjoyable showering experience regardless of the showerhead you use.

You can comfortably use a rainfall showerhead with this slim and compact water heater.

At the front of this device, you have the temperature control that allows you to adjust the water temperature with ease.

There is also a water temperature indicator, although it simply displays a light meter and not the actual water temperature.

Pros:

• Small and compact. Can be installed in a small bathroom
• Decent flow rate at 4.0 GPM and energy efficient
• Very beginner-friendly and easy to install

Cons:

• Does not display actual water temperature
• Not as aesthetically pleasing when compared to others

6. Rheem RTEX-18 – Accurate Temperature Control

Photo: Rheem

• Power: 240 V
• Flow Rate: 4.4 GPM
• Dimensions: 4 inches x 15 inches x 19 inches

The Rheem RTEX-18 may not be the biggest electric tankless water heater that we have in this review, but it is still quite performing.

Specifically, it really shines in the flow rate department with a flow rate of 4.4 GPM, which allows it to output a lot of water really fast to your showerhead.

Moreover, what we like about this water heater is its granular control on the temperature. Indeed, you can increase or decrease the temperature up to 1° of accuracy, which is truly remarkable.

The front has a digital display that will show you the exact water temperature. When it comes to installation, no problem because it uses standard 3/4-inch threaded connectors at the bottom.

Pros:

• Accurate temperature control with a 1° accuracy
• The high flow rate of 4.4 GPM
• Digital front water temperature display
• Easy to install

Cons:

• Difficult to get a replacement fuse

7. Bosch Tronic 3000 Series – Best Space Saving Water Heater

Photo: Bosch

• Power: 7.2 kW, 240 V
• Flow Rate: 1.5 GPM
• Dimensions: 6.5 inches x 12.25 inches x 3 inches

One of the biggest advantages of this Bosch electric tankless water heater is its ability to be installed anywhere. It is small and compact, so it will not consume a lot of installation space.

Furthermore, this unit has been built in such a way that it can be installed like a regular shower heater, or installed under your bathroom or kitchen sink.

It has a front red LED indicator that will show you when it is operational, and the device itself is quiet in operation, so it can comfortably be used at night.

According to the manufacturer, it is 98% efficient, which means that only 2% of electricity goes to waste in terms of heat and sound. In addition to the fact that it uses only 7.2 kW of power, which means that it is very cost-effective to run.

Furthermore, this top-rated electric tankless water heater does not require a high-water pressure to operate optimally, so it can be used anywhere.

Pros:

• Uses only 7.2 kW of power and 98% energy efficient
• Small and compact. Can be installed anywhere
• Available in different sizes to suit your need

Cons:

• Weak performance
• The low flow rate of 1.5 GPM

​Electric vs. Gas Tankless Water Heater

Photo: mydecorative.com

Both the gas and the electric tankless water heater are 2 popular types of water heaters on the market. But which one do you need? Let’s find out!

1. Electric Tankless Water Heater

Advantages

Safe: One of the biggest advantages of the electric tankless water heater is its safety. Indeed, since this type of water heater does not emit harmful CO2, it is safer to use, especially in a small and confined the bathroom.

Price: The electric tankless water heater is also more affordable than its gas counterpart. This is mostly because it is easier to make an electric tankless water heater because it contains simple electric parts.

Ease of Installation: All you have to do to install the electric tankless water heater is connecting the water inlet and outlet connections, and then connected to the power grid. That’s it!You do not have to install a venting system, and it is incredibly easy to install.

Disadvantages

Electricity Consumption: The big disadvantage of the electric tankless water heater is obviously its electricity consumption. If electricity is expensive where you live, then an extended use of the electric tankless water heater may result in a high electricity bill.

Not as powerful: When compared to its gas-powered counterpart, the electric tankless water heater is simply not as powerful. Therefore, it has a lower temperature rise, and if you live in an area where the water gets very cold, it may take some time to heat that water.

Frequent Maintenance: You will need to perform frequent maintenance in your electric tankless water heater to prevent it from clogging. This is due to hot water that causes calcium and limescale buildup.

2. Gas Tankless Water Heater

Advantages

High performance and heavy-duty: This type of tankless water heater is known for its high performance. Indeed, it is able to heat cold water very fast, which makes it an ideal solution for those who live in very cold environments.

Lower cost: Since natural gas is normally less expensive than electricity, running a gas-powered tankless water heater is usually more cost economical.

Higher flow rate: Due to its high power, it is able to heater more water faster, so a gas tankless water heater is able to heat more water quicker.

Disadvantages

Expensive: Since there are more complex parts in the gas tankless water heater, it is usually more expensive as well because it is more complicated to make.

Emit CO2: One of the biggest disadvantages of this type of heater is that it emits CO2, which may be dangerous to the health if inhaled for an extended period of time.

Requires a venting system: You will need to install a venting system with this type of water heater. It may also be expensive to do so, and you may need professional help for this, which makes it not as easy to install when compared to an electric tankless water heater.

All in all, choose a gas tankless water heater if you live in an area where the water is very cold, and you require a high flow rate for your shower heads.

Also, be prepared to install the venting system if you choose to go with a gas model.

For anything else, an electric tankless water heater is more than adequate.

How to Buy the Best Electric Tankless Water Heater

Photo: Bosch

1. Your Demand

Identifying your demand is one of the most important factors to consider when purchasing an electric tankless water heater.

This is because not all electric water heaters behave the same, and some are more heavy duty and high performing than others.

For example, if you are buying an electric tankless water heater for a big family, then you need to go with a highly rated model that will be able to handle the water heating demand.

2. Flow Rate

The electric tankless water heater does not have a very high flow rate when compared to its gas counterpart.

However, it is still able to output a reasonable amount of flow rate ranging from 1.5 GPM anywhere to 5 GPM for some of the best electric tankless water heaters on the market.

If you have demanding showerheads like a rainfall showerhead, then we recommend that you go with a model that has a higher GPM.

3. Temperature Rise

The temperature rise in an electric tankless water heater is simply how fast the heater is able to increase the temperature from groundwater temperature to its chosen temperature setting.

The higher the temperature rises, the more performing the water heater can be assumed to be.

4. Energy Savings

Since the electric tankless water heater uses electricity, it stands to reason that you go with a model that is energy-saving.

This is especially important if you have a big family who will be using the water heater for an extended period of time. It will quickly add up to your electricity bill.

The energy consumption is usually measured in kilowatts of power and the smaller the value, the less electricity it will use.

However, keep in mind that a lower powered electric tankless water heater will have a low temperature rise as it will take more time to heat groundwater to your desired temperature.

5. Display

There are many electric tankless water heaters that will provide you with a display at the front of the device.

This display normally shows the temperature of the water as well as its flow rate. While this is not mandatory, it always helps to know the current water temperature and water flow rate.

Therefore, as far as possible, it is advisable to go with an electric tankless water heater that has a display.

6. Temperature and Flow Rate Adjustment

At some point or the other, you will feel the need to adjust the water temperature as well as the flow rate.

This is especially true if you live in a region where the temperature of the groundwater very often.

Therefore, choose a model that has a way to quickly and easily adjust the water flow rate as well as the temperature.

7. Warranty

Since it can be difficult to repair an electric tankless water heater, check out if the manufacturer offers you a form of warranty.

Most reputable water heater manufacturers have no problem backing up their product with at least 1-year warranty.

However, there are still other manufacturers that will offer you a lifetime warranty so definitely get those.

Conclusion

The electric tankless water heater is one of the easiest water heaters to use.

You will have no problem installing this type of heater because it uses traditional 1/2- or 3/4-inches water connectors.

With this type of water heater, you can quickly and easily adjust the water flow as well as water temperature to your liking.

In fact, the whole family can use it because it is very easy and straightforward to use.

It also works with all types of showerheads, and most modern models are quite energy efficient and reliable.