BEST ELECTRIC TANKLESS WATER HEATERS
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WHAT IS AN ELECTRIC TANKLESS WATER HEATER?
Tankless water heaters – also known as on-demand or point-of-use heaters, are devices located in your home’s water pipes that heat water as and when it is needed (rather than the traditional method of heating and storing hot water). Such is the power of the heating element, that many models can heat 3-5 gallons of water per minute to a piping hot temperature. Because there’s no wasted energy, tankless heaters are more cost-effective.
This guide will outline the best on the market, no matter your home and family circumstances. We have pages that go more in-depth on electric vs. gas water heaters and tankless water heaters if you would like to know more about each.
METHODOLOGY
In order to cultivate this list, we focused on a variety of different criteria:
- Price
- Reliability
- Warranty
- Flow Rate
- Size
- Power
Because not everybody has the same requirements for a tankless heater, we created a variety of different categories. We surveyed many different models on the market to find a clear overall winner, as well as a winner in three different sub-categories.
OUR OVERALL WINNER
EcoSmart has built a reputation within the industry for building seriously impressive tankless heaters, and this model is no exception. True to the name, this model is both Eco and Smart. The ECO 27 has a flow rate of 5.3 GPM, which will be more than enough for all but the largest households. Moreover, a price point of less than $500 is an impressive thing.
What’s truly remarkable about this device is that whatever the angle from which you examine it, it comes out looking impressive. Want a great flow rate? It has that. Want a low running cost? It has that too. Want something that’s great for the environment? It’s EcoSmart for a reason. And what about a good price point? That’s what you get. This was the clear choice for an overall winner.
QUICK COMPARISON CHART
 EcoSmart ECO 27 |  Rheem RTEX-18 |  Stiebel EltronTempra 29 Plus |  Bosch Mini-Tank | |
|---|---|---|---|---|
| COST | $489 | $429 | $799 | $209 |
| Wattage | 27 kw | 18 kw | 28.8 kw | 1.44 kw |
| max amperage draw | 112.5 | 75 | 120 | 12 |
| warranty | Lifetime (parts - limited) | 5 year (heat exchanger); 1 year (parts) | 7 year (leakage); 3 year (parts) | 6 year (unit); 2 year (parts) |
| flow rate (GPM) | 5.3 | 4.4 | 3.7 | 0.11 |
BEST OVERALL ELECTRIC TANKLESS WATER HEATER
EcoSmart ECO 27 with
Patented Self Modulating Technology
Of all of the tankless heaters we reviewed, this one seemed to dominate every category. When it comes to flow rate, for example, this one offers 5.3 GPM, well above other comparable heaters. The running costs, installation costs, and even upfront costs are low, and the warranty length is long. Regardless of the category, the EcoSmart heater was in the running.
So, if you’re converting your house to a tankless system, this water heater should be the first one you consider.
$
COST
The EcoSmart ECO 27 electric tankless water heater costs around $489.
ECO 27 Specs:
- Dimensions: 17 x 17 x 3.6 inches
- Output water temp. range: 80°F - 140°F
- Weight: 14 pounds
- Voltage: 240
- Warranty: Lifetime warranty on electronics, exchanger and element. Warranty only covers cost of heater; does not cover labor or any incidental damages.
PROS
- Heat. This model can get 3 GPM even in the coldest climates, making it a great option for those in mild and cold parts of the country.
- Self-modulation. This model adjusts pressure and power to keep a consistent output.
- Savings. The modulation (and precision heat settings) combine to make for low running costs.
CONS
- Overkill. In warm areas, this model may be too powerful for your needs.
What People are Saying:
“Does a great job heating the water. If shower is being utilized and second faucet gets turned on, you have a 2-3 second delay on average until it re-calibrates the heat setting for the added demand.”– Amazon reviewer
“I own a 3 bedroom, 2 bath home. With a family of 4, this little water heater provides more than enough hot water for us even with 2 showers going and washing dishes. Saved roughly 15-18% on my electric bill since going tankless.” – Home Depot reviewer
BEST SELF-INSTALL MODEL
Rheem RTEX-18
Converting your entire home to a tankless system can be daunting, so we searched for a water heater that you can install yourself to cut down costs. However, professional install is always recommended if you’re having doubts about your abilities. The Rheem RTEX-18 is a great budget option for the whole house – it is small enough to be unobtrusive, and it provides enough hot water when you need it.
A 4.4 GPM flow rate is a solid number, and can be supplemented with smaller additional models if the need increases. Either way, if this is your first tankless system and you are a little unsure about the whole process, the Rheem RTEX-18 should set your mind at ease.
$
COST
The Rheem RTEX-18 electric tankless water heater costs about $429.
Rheem RTEX-18 Specs:
- Dimensions: 3.5 x 14.5 x 18.25 inches
- Output water temp. range: 80°F - 140°F
- Weight: 11 pounds
- Voltage: 240 volts
- Warranty: 5 Year (heat exchanger); 1 Year (parts)
PROS
- Price. The upfront cost of this model is competitive.
- Space savings. The model is designed to be small and therefore doesn’t take up too much space.
CONS
- Flow rate adjustments. In order to get the water temperature that you desire, you may need to adjust the flow rate a time or two until you find your sweet spot.
What People are Saying:
“The product is easy to install but you do need 4 40 amp greasers and space for them in your panel. As long as you have the needed power the system works ok. I loved being able to get rid of my 50 gallon tank and have more storage space as my home is small.” – Home Depot reviewer
BEST ELECTRIC TANKLESS WATER HEATER FOR POWER
Stiebel Eltron Tempra 29 Plus
If you have a big family or high water output, this is a solid option for you. The Stiebel Eltron is designed for a five or six-person house, meaning it can pack enough of a punch to keep you all warm as multiple showers run simultaneously. Of all the models surveyed, this is the one that consistently came back as having enough power whatever the circumstances.
This is also true if you have a large house. Some whole-house tankless heaters struggle to physically get the water to the furthest parts. Not the Steibel Eltron – whatever you ask of it, it will deliver.
$
COST
The Stiebel Eltron Tempra costs around $799.
Stiebel Eltron Tempra Specs:
- Dimensions: 16.54 x 4.61 x 14.53 inches
- Output water temp. range: 86°F - 140°F
- Weight: 10.37 lbs
- Voltage: 220 volts
- Warranty: 7 years leakage / 3 years parts
PROS
- Noise. This model is one of the quietest on the market.
- Venting There is no venting required for this model, in comparison with almost every other tankless heater out there.
- Modulation The auto-modulating unit provides constant energy savings.
CONS
- Price. At $799, this is one of the pricier options on the market.
- Technology. The automatic management system may not be as reliable as it could be.
What People are Saying:
“This unit provides hot water in no time. The water stays hot for the entirety of use… no cold shocks!! This was an easy install and has freed space in the garage. Our only regret is not doing this install sooner!”
– Lowe’s reviewer
“Works really well. Run two showers at once and definitely keeps up. I am located in south Texas so water temps are 75 and above.” – Home Depot reviewer
BEST MINI-TANK
Bosch Electric Mini-Tank
Tronic 3000 T 7-Gallon (ES8)
The mini-tank is a great entry-level tankless system. Get one of these for your kitchen sink and see how quickly you come to depend on it. If this is how you decide to proceed, then the Bosch is absolutely the one for you. At around $200, this one won’t break the bank and the 0.11 GPM is a respectable output. On top of that, the Bosch design is both reliable and effective – a 6-year warranty guarantees that.
If you want to give the tankless method a try, this Bosch model will show you what these things are capable of.
$
COST
The Bosch Mini-Tank model cost is around $209.
Bosch Electric Mini-Tank Tronic Specs:
- Dimensions: 17.5 x 17.5 x 14.5 inches
- Output water temp. range: 65°F - 145°F
- Weight: 29.5 lbs
- Voltage: 120 volts
- Warranty: 6 year warranty on unit, 2 year warranty on parts
PROS
- Price. At around $200, this model is a great entry-level device.
- Design. This model is compact, sleek, and fits neatly under a sink.
- Easy setup. Not only is this easy to install, but it’s easy to adjust if you need to move it.
CONS
- Output. This model’s size means it can only deliver water to one sink at a time.
- Showers. This model doesn’t work on showers. Its primary use is for sinks, meaning it may be simply too limited for your family.
- Display. A common complaint is that the temperature is displayed only in Celsius, not in Fahrenheit.
What People are Saying:
I can’t speak to the longevity yet but so far I should have put this in years ago. Instant hot water to the kitchen sink which is over 40 feet from the main hot water tank. With the plumbing running through the crawlspace I used to have to wait a minute or two for hot water. Not any more!” – Amazon reviewer
“I have had the heater installed for about 2 weeks and it is working great. It supplies all the hot water we need. I would recommend this water heater for anyone wanting to save money on electricity and still have plenty of hot water.” – Lowe’s reviewer
Tankless water heaters are very much the future of home water heating. The on-demand service they provide means they are more efficient, more environmentally friendly, and more cost-effective. On top of that they have practical benefits, such as never running out of hot water nor having to wait for a tank to refill with hot water.
If you do decide to make the switch, you may be surprised at how low the cost is – in most cases, a tankless water heater is cheaper than a tank water heater. Given this, the next time your water heater breaks, it may be time to make the switch.