In this article, I’ll review 8 best whole house electric tankless water heater options in 2020 from 4 internationally trusted brands.
For each option, I’ll explain the tech details, Pros & Cons, and regional information!
A comprehensive Buyers Guide including a unique FAQ section is also provided at the end discussing the best options for different scenarios!
If in a hurry, see our Editors Pick and Comparison Table at first!
For those that live in a big house with many occupants, you know that hot water is a precious commodity. If that’s you, then you may be looking for the best whole house electric tankless water heater in 2020.
Hot water can be hard to come by, certain times of the day. It can be something that you sit around waiting for.
You may be burdened by so many fixtures in the house needing hot water, perhaps a big, clunky, slow hot water tank.
Go tankless and go electric. You’ll have no regrets.
The rarity of ‘immediate hot water’ will become so commonplace that you’ll wonder why it was ever a problem.
But how exactly do you find a great whole house electric tankless water heater in 2020?
It all starts with you and your specific situation.
There won’t be one ‘be-all end-all’ answer for everyone. There is no one right answer. There are many right answers. Different answers for different situations.
So, let’s peel away and get to the details of your specific situation, your specific wants and needs!
Best Whole House Electric Tankless Water Heater on a Budget
EcoSmart ECO 27
A fairly small, lightweight, and budget option, the ECO 27 uses EcoSmart’s self-modulating technology, so it only uses energy when water needs to be heated.
This option may not be great for powering an entire large home in all parts of North America but depending on where you live it could.
It is highly energy-efficient saving you money in the long run.
Read the review section for in-depth tech details and regional information!
Overall Best Whole House Electric Tankless Water Heater
Rheem RTEX-36
A powerful yet affordable option from Rheem, the RTEX-36 uses an advanced self-modulation technology that adjusts power based on the hot water demand.
You’ll also have an external digital thermostat with an LED screen that will let you change the temperature settings in one-degree increments.
This is my favorite pick from the list!
See the review section for in-depth tech details and regional information!
Best Budget Whole House Electric Tankless Water Heater
For Low-Flow Family of 3 or 4
EcoSmart ECO 36
(If you live in Canada and Northern U.S.)
If you live in areas where the groundwater temperature is 42 and basically all the way up to about 60 Fahrenheit… the cheapest option for a low-flow family of three or four will be the EcoSmart ECO 36.
Refer to the review section for in-depth tech details and regional information!
EcoSmart ECO 27
(For the rest of the U.S.)
If you live anywhere where the groundwater temperature is normally higher than 60 Fahrenheit, then you can go with the EcoSmart ECO 27.
This option may not be great for powering an entire large home in all parts of North America but it is normally doing fine for a low-flow family of three or four for the rest of the U.S.
See the review section for in-depth tech details and regional information!
Best Whole House Small Electric Tankless Water Heater
(Smallest in Depth)
Any Rheem models on the list!
You can pick the right one depending on the power you need and the area you live from the following.
RTEX-24
RTEX-27
RTEX-36
See the review section for in-depth tech details and regional information!
Best Whole House Small Electric Tankless Water Heater
(Smallest in Height)
Black + Decker 36 kW
The powerful and lightweight Black + Decker 36 is claimed to be ideal for a 4-bedroom house and up to 8 simultaneous appliances.
This, of course, depends on the fixtures, but it is very doable.
Refer to the review section for in-depth tech details and regional information!
Best Whole House Small Electric Tankless Water Heater
(Smallest in Width)
Any Stiebel Eltron model on the list!
You can pick the right one depending on the power you need and the area you live from the followings.
Stiebel Eltron Tempra Plus 29 kW
Stiebel Eltron Tempra Plus 36 kW
See the review section for in-depth tech details and regional information!
Best Whole House Small Electric Tankless Water Heater
(Smallest in Cubic Inches)
EcoSmart ECO 27
A fairly small, lightweight, and budget option, the ECO 27 uses EcoSmart’s self-modulating technology, so it only uses energy when water needs to be heated.
It is highly energy-efficient saving you money in the long run.
The ECO 27 may not be great for powering an entire large home in all parts of North America but depending on where you live it could.
Read the review section for in-depth tech details and regional information!
You may know a good deal about electric tankless water heaters. Maybe you don’t know much at all. That part isn’t so essential.
You need to know your house. You need to know you. And you need to know your family members or other housemates.
We’re going to review several different electric tankless water heaters. I’ll explain specs and details on all these different water heaters and we’ll narrow down the choices.
We’ll apply that knowledge to your living situation and we’ll find you the best choice. You’ll have to keep some things in mind while we go over this list.
What are the high-hot-water-traffic situations like in your household?
What’s the maximum number of showers you may have going at once?
What’s the maximum number of appliances using hot water you may have going at once?
What types of appliances are those?
Are any of those appliances low-slow or water-saver types?
Do you have several kids getting ready for school in the morning?
Does your schedule entail that you be getting ready around the same time as many others?
And where do you live?
What’s your region like?
Is it a colder region that will take some power to heat up the colder ground water?
And what’s your budget?
Don’t worry if you don’t have all those answers right now. We’ll go over everything and make it crystal clear.
There are many options, so you’ll definitely find something on this list that you’ll love.
So, without further ado, let’s get to it and find you the best whole house electric tankless water heater in 2020!
Specific to your house, of course.
Let’s start with a short overview of the selected small water heaters and a helpful table comparing their specifications.
Read also: Best Indoor Tankless Water Heaters
Read also: Best Small Tankless Water Heaters
Read also: Best Outdoor Tankless Water Heaters
Read also: Best Rinnai Tankless water Heaters
What is the Best Whole house Electric Tankless Water Heater in 2021?
Quick Answer:
- EcoSmart ECO 27 Electric Tankless Water Heater | Best on a Budget
- EcoSmart ECO 36 Electric Tankless Water Heater | Best Budget Option (for Canada & Northern U.S.)
- Stiebel Eltron Tempra Plus 29 kW Tankless Water Heater | Smallest in Width
- Stiebel Eltron Tempra Plus 36 kW Tankless Water Heater | Smallest in Width
- Rheem RTEX-24 Tankless Water Heater | Smallest in Depth
- Rheem RTEX-27 Tankless Water Heater | Smallest in Depth
- Rheem RTEX-36 Tankless Water Heater | BEST OVERALL & Smallest in Depth
- BLACK + DECKER 36 kW Self-Modulating Electric Tankless Water Heater | Smallest in Height
Comparison Table for the Best Whole House Electric Tankless Water Heaters in 2021
| Electric Tankless Water Heaters | View on Amazon | Kilowatt (kW) | Maximum GPM | (Depth, Height, Width) in inches | Weight (Pounds) |
|---|---|---|---|---|---|
| EcoSmart ECO 27 |
 
|
27 kW | 6.5 GPM | 3.625 x 17 x 17 | 14.7 lbs. |
| EcoSmart ECO 36 |
 
|
36 kW | 8.7 GPM | 3.625 x 17 x 21 | 18.35 lbs. |
| Stiebel Eltron Tempra Plus 29 |
 
|
29 kW | 6 GPM | 4.6 x 16.6 x 14.5 | 17.6 lbs. |
| Stiebel Eltron Tempra Plus 36 |
 
|
36 kW | 7.5 GPM | 4.6 x 16.6 x 14.5 | 19 lbs. |
| Rheem RTEX-24 |
 
|
24 kW | 5.9 GPM | 3.5 x 18.25 x 17.63 | 17.8 lbs. |
| Rheem RTEX-27 |
 
|
27 kW | 6.6 GPM | 3.5 x 18.25 x 17.63 | 17.8 lbs. |
| Rheem RTEX-36 |
 
|
36 kW | 8.8 GPM | 3.5 x 18.25 x 21.63 | 22.7 lbs. |
| BLACK + DECKER 36 |
 
|
36 kW | 7 GPM | 4.5 x 14.75 x 23.25 | 16.75 lbs. |
Best Whole House Electric Tankless Water Heater in 2021
1. EcoSmart ECO 27 Electric Tankless Water Heater | Best on a Budget
From a great brand, EcoSmart, we’ll start with the ECO 27!
Let’s first mention the price of about $465. An important thing to mention right off the bat, this is the cheapest model on this list!
For those of you looking for something on a slight budget, keep the ECO 27 in mind!
It is also one of the best small tankless water heaters available!
TECH SPECS
All these tankless options are much smaller than their larger tank counterparts. But among the list of 8 here, they range in size a bit.
The ECO 27 has dimensions of 3.625 inches, 17 inches, 17 inches (depth, height and width), making it the smallest in cubic inches.
A fairly smaller option on the list, especially in terms of the depth!
It’s one of the shallowest options, good to know if you don’t want your tankless water heater jutting out in the way. And at just 14.7 lbs., the lightest option here!
The ECO 27 uses EcoSmart’s self-modulating technology, so it only uses energy when water needs to be heated.
That saves energy and saves your money!
You’re working with 27kW on this model which can give you a maximum 6.5 GPM (gallons per minute)! Though, that does depend on where you live.
REGIONAL INFO
Keeping in mind that this is the cheapest option, it isn’t the least powerful option. That’s great, but it’s also far from the most powerful.
This option may not be great for powering an entire large home in all parts of North America but depending on where you live it could.
And for the lowest cost of all the models on this list, that may entice you to claiming this to be the best whole house electric tankless water heater in 2020.
According to EcoSmart, if you live in a region where the ground water temperature is an average of 62 degrees Fahrenheit, you can achieve around 4.2 GPM.
Meaning you can operate two showers at once with this model. Or you could run one shower along with two-bathroom faucets simultaneously.
If any of your appliances are low-flow, you’d likely be able to run more than this 2-3 fixtures average.
This applies to a large portion of the U.S., mainly including southern areas such as most of Arkansas, most of South Carolina and much of northern Texas.
But it also includes many parts in California and even as far north as San Francisco and Oakland.
Typically, the farther south you travel, the higher the ground water temperature will be, and the more you can get out of this model.
Ground water temperatures of 67 degrees Fahrenheit can achieve 4.8 GPM, like in Mobile, New Orleans and Austin.
Ground water temperatures of 72 degrees can get 5.5 GPM, cities like Orlando and Los Angeles.
And the maximum of 6.5 GPM can be achieved if the ground water temperature is 77 degrees Fahrenheit in your area.
Miami, Hawaii, Puerto Rico, areas like this can get three showers operating easily, and a low-flow faucet on top of that!
If you live in any of these areas and 3 to 4 fixtures is about all you’ll need at a time, then this is great and low-cost option for you!
Pros
- Cheapest option
- Lightest option and smallest in cubic inches
- Fairly powerful for smaller model
- Self-modulating technology
Cons
- Not the most powerful
- Can’t achieve the highest GPM
2. EcoSmart ECO 36 Electric Tankless Water Heater | Best Budget Option if you live in Canada & Northern U.S.
Keeping in the great EcoSmart brand and moving up to the ECO 36!
As you likely guessed, this model is bigger, it will do more, and yes it does cost more.
Just about $563 though, which is a fair price for what it can accomplish.
TECH SPECS
Still a nice shallow option like the ECO 27. The dimensions are 3.625 inches, 17 inches, 21 inches (depth, height, width) meaning it’s the same depth and height and a bit wider.
Weighing in at 18.35 lbs. means it’s a bit heavier too.
Same self-modulating technology also means you’re saving energy and saving money in the long run as your model will only use energy when water needs to be heated.
And this model is operating at 36kW. This is a more powerful option as you can see.
And it’s listed as having a maximum GPM of 8.7. Once again, depending on where you live.
So, why don’t we take a look at where you live.
REGIONAL INFO
Where the ECO 27 could achieve at least 4.2 GPM anywhere with an average ground water temperature of 62 degrees Fahrenheit or higher, the ECO 36 can do the same anywhere with an average ground water temperature of 47 degrees or higher.
This means, you could be living as far north as the likes of Providence, New York City, Chicago and Portland and you can run two simultaneous showers.
One shower and two-bathroom faucets would work, and if any appliances are low-flow, you can get even more fixtures providing hot water all at once!
Anywhere further north, like most of Minnesota, Wisconsin, and all of Canada… you’ll only be able to get a shower and kitchen sink to give you hot water at the same time.
If you need more than just that operating at once… you could consider some low-flow options.
A lot of the southern U.S. can get three showers to run at once.
And if it’s a family of four this is serving, and all four family members shower at once, Puerto Rico, Hawaii and Miami will have no problems with the ECO 36!
Pros
- Cheapest 36kW option
- Very high GPM and very powerful
- Great to use all over North America
- Self-modulating technology
Cons
- Doesn’t have the best tech of all the options
- Not the most powerful or highest GPM of all 36kW options
3. Stiebel Eltron Tempra Plus 29 kW Tankless Water Heater | Smallest in Width
From Stiebel Eltron, the Tempra Plus line has some amazing options. First on our list, the Tempra Plus 29.
This model will be a little lower on the list in terms of power, but it can still get plenty done.
For the price of about $763, it’s pricier than some other options, but the brand does have some great qualities.
TECH SPECS
Though the weight of 17.6 lbs. is heavier than the comparable ECO 27, the dimensions of 4.6 x 16.6 x 14.5 inches (depth, height, and width) make this model shorter and skinnier.
If you’re trying to keep your tankless water heater out of the way, and taking up as little space as possible, this could be an option for you.
The Tempra Plus 29 has self-modulation to save energy and save you money.
And it also has advanced flow control.
So, if the demand on hot water is more than what the model can handle, rather than surprising anyone in the household with cold water, the flow of water is automatically decreased to the fixtures so hot water can keep on flowing.
No more awful, cold surprises in your morning shower!
This model operates on 29kW and has a maximum 6 GPM, which is the second lowest of all eight options on the list.
Now, let’s look to see what this means for your region.
REGIONAL INFO
Now, the number of fixtures you will be able to serve will depend on what the GPM flow rate is for each individual fixture.
But working with what most fixtures tend to be, the Tempra Plus 29 assures it can serve at a minimum, two showers anywhere in North America.
Perhaps this model costs a bit more, but for those in Canada, Alaska, and the Dakotas for example…
if you have a large home and tend to have two people getting ready at a time during your busy weekday mornings, you have now found a tankless water heater that can help you out!
Other northern areas in the U.S. can even have the luxury of running a bathroom sink in addition to those two showers!
Places like all of Idaho, Nebraska and Ohio… that’s three fixtures at once with ease!
And for all of the southern U.S., you can run three, maybe even four showers at a time with no problem. This includes all of Texas, Florida, Mississippi, The Carolinas, and plenty more!
Pros
- Great tech with self-modulation and advanced flow control
- GPM isn’t the tops but still powerful and can serve two showers minimum anywhere in North America
- One of the thinnest options
Cons
- Pricier option
- A lower option in terms of GPM
- One of the largest in depth
4. Stiebel Eltron Tempra Plus 36 kW Tankless Water Heater | Smallest in Width
How about a step up within Stiebel Eltron’s Tempra Plus line to the 36!
Another model with a lot to love.
It costs about $829, which is the most expensive water heater on our list, but you’ll see there’s very good reason for this price.
TECH SPECS
The dimensions of 4.6 x 16.6 x 14.5 inches (depth, height, width) are the same as the last model from Stiebel Eltron, so you won’t be sacrificing any space.
A nice plus, considering you’ll be getting more power!
It does weigh about 19 lbs., so it is a tad heavier.
Same great self-modulation technology saving money for you to keep in your wallet, and not wasting more energy than is needed.
And it of course, has the same great advanced flow control that guarantees no cold-water surprises with your fixtures if the demand for hot water is too high.
Just a reduced flow of water to fixtures until the demand drops.
Similar to the EcoSmart option, this model operates on 36 kW. And it can achieve a maximum 7.5 GPM.
Not claiming to be as high as the ECO 36, but with advanced flow control, the Tempra Plus 36 claims to be able to handle a lot!
REGIONAL INFO
Now, the Tempra Plus 36 is going to guarantee you that if you live anywhere in North America, you’ll be able to run two showers along with a bathroom sink.
Of course, you’ll always want to check the flow rate of your appliances, but this is fantastic news for all those in Maine, New Hampshire, Montana, and yes of course Canada.
That’s three different fixtures that can all access hot water during your busy morning routines.
And anywhere where the ground water temperature is on average 52 degrees Fahrenheit or higher, you’ll be able to run at least three showers at a time.
Even places as far north as Newark, Pittsburgh, Detroit, and Seattle… the Tempra Plus 36 can give a three-person household all they need for any morning.
And large portions of North America will be able to run three showers along with a sink or even four showers along with a sink, so long as the ground water temperature is around 62 degrees Fahrenheit or more.
Or for those trying to squeeze in some chores while you get ready for work in the morning… a dishwasher runs at about the same GPM as a shower.
Residents of Charleston, Nashville, Oklahoma City, Oakland and more… run the dishwasher, take a shower, have another family member take a shower, have another family member use the sink. It’s all good!
Southern Texas, southern Florida, Hawaii and more… your 4 to 5 fixture possibilities mean you’re really not going to have to worry about when you use hot water much at all.
Pros
- Great tech with self-modulation and advanced flow control
- Fairly high GPM overall
- One of the thinnest options
Cons
- Most expensive
- Among the 36 kW options, lower GPM and power
- One of the largest in depth
5. Rheem RTEX-24 Tankless Water Heater | Smallest in Depth
Let’s talk about the brand Rheem. This is quite the loveable brand with plenty of options big and small. Shall we start with the RTEX-24?
This model costs around $490, making it one of the cheapest models on the list.
Those on a budget may want to keep their eyes on this model.
TECH SPECS
One interesting thing to note are the dimensions of the RTEX-24.
They are 3.5 x 18.25 x 17.63 inches (depth, height and width) and along with the following model we’ll review, the RTEX-27, it’s the smallest in terms of depth.
Hide this little number away, it won’t get in anyone’s way. And it weighs about 17.8 lbs., so it’s definitely on the lighter side.
The 24 kW this model operates on is the lowest on the list, but that won’t stop this Rheem from getting as much done in your whole house as possible.
The maximum GPM of 5.9 is the lowest on this list. But the RTEX-24 really can get a lot more done than you’d originally think.
It touts advanced self-modulation technology in order to adjust the power in terms of what the hot water demand is.
It also has an external digital thermostat with an easy-to-operate and quite clear LED screen.
Change the temperature settings in 1-degree increments from 80 to 140 degrees Fahrenheit.
REGIONAL INFO
In areas like Southern Florida, Southern Texas, Puerto Rico, and Hawaii, the RTEX-24 should be able to handle three showers at one time.
If it’s a three-person household you live in, and every one of you is only running hot water from one appliance at a time, then the RTEX-24 may be the best whole house electric tankless water heater in 2020 for you.
Even in most of the southern U.S., like the southern portions of Georgia, Alabama, Louisiana, California, all of Florida, and plenty more areas, you can run two simultaneous showers.
If your house doesn’t call for more than two showers at once, or one shower and two sinks at once, then the RTEX-24 could be a smart choice!
Going any farther north and you’ll be limited to the number of fixtures that can access hot water at once.
That is unless you have many low-flow options.
At this low price, the RTEX-24 is definitely a great choice for those in the south to make for their whole house.
Pros
- One of the cheapest options
- One of the smallest in terms of depth
- Great inexpensive option for much of the southern U.S.
Cons
- Lowest GPM on the list
- One of the largest in height
- Lowest kW and power
6. Rheem RTEX-27 Tankless Water Heater | Smallest in Depth
Moving up a rung on the Rheem ladder, we reach the RTEX-27.
Priced at about $620, this model finds itself right around the middle of the pack in terms of cost.
Mid to low-end for power… but Rheem will tell you, the price tag is indicative of the quality product you’re receiving.
TECH SPECS
As mentioned with the RTEX-24, you have the dimensions of 3.5 x 18.25 x 17.63 inches (depth, height, width) with this model, which makes it tied for the smallest in terms of depth.
A great feature if you’re looking to keep your water heater as flush with the wall as possible.
The RTEX-27 also weighs about 17.8 lbs. On the lighter side in terms of the whole list, and the same size as it’s less powerful predecessor.
So, they packed more tankless water heater goodness into the same frame!
You get the same advanced self-modulation technology that adjusts the power based on the hot water demand.
And you have the same external digital thermostat with LED screen allowing you to change the temperature settings in 1-degree increments from 80 to 140 degrees Fahrenheit.
This 27-kW model can achieve at it’s very best, 6.6 GPM!
REGIONAL INFO
With the RTEX-27, you’ll be looking at similar outputs per region as you were with the ECO 27.
In areas with an average ground water temperature of 62 degrees Fahrenheit or higher, you’ll be able to run at least two showers at once.
Or you could run the dishwasher while running a shower, or a shower and a couple of bathroom sinks!
This includes areas in the southern U.S. like most of Missouri, Texas, Arkansas and even in Las Vegas.
The farther south you go, the more likely you can run another appliance on top of two running showers. The likes of Jacksonville, Baton Rouge and parts of southern New Mexico.
And like the ECO 27, you can achieve the maximum GPM in places like Miami, Hawaii, and of course Puerto Rico and other Caribbean islands!
With the 6.6 GPM you’ll be able to run three showers and a low-flow faucet at once!
Four fixtures needing to be run in the Caribbean? The RTEX-27 might be a perfect choice for you!
Pros
- Decent GPM and great tech from Rheem
- One of the smallest in terms of depth
- Step up in power from the RTEX-24
Cons
- Still isn’t the most powerful non-36 kW option
- One of the largest in height
7. Rheem RTEX-36 Tankless Water Heater | Best Overall & Smallest in Depth
And yes, Rheem does have an even more powerful option waiting for those of you that need more power.
The RTEX-36 is the top of this particular line.
It costs about $797 making it the second most expensive model on the list. Let’s explore the details on this one.
TECH SPECS
To start with the dimensions of 3.5 x 18.25 x 21.63 inches (depth, height, width), this model has the same depth and height as the previous two, but it is a good deal wider.
You’ll want to make sure you have some extra room for it, but remarkably, it is the same depth making it another model tied for the smallest in that respect!
It weighs about 22.7 lbs., so it’s definitely got a bit more heft to it than the other Rheem models. In fact, it is the heaviest model on the whole list.
Just like the two Rheem models before, you’ll have advanced self-modulation technology with the RTEX-36.
Technology that adjusts the power based on the hot water demand so if you try using more than it can handle, no problem! But it will be hard to use more than this big guy can handle.
You’ll also have the same external digital thermostat with an LED screen that will let you change the temperature settings in 1-degree increments from 80 to 140 degrees Fahrenheit.
The RTEX-36 is a 36 kW model that can achieve 8.8 GPM at it’s very best!
REGIONAL INFO
Time to check your region’s ground water temperature! And time to check the GPM flow rate of your appliances!
Going off averages, as long as you live in North America and you aren’t too North-Pole-adjacent… the RTEX-36 is going to allow you to run two showers along with another appliance like say, a bathroom faucet or low-flow kitchen sink.
Those of you in the often-cold Canadian cities like Toronto, Montreal and Vancouver and cities in the U.S. like Minneapolis and Buffalo can make this their reality.
Residents of locations where the ground water temperature is on average 52 degrees Fahrenheit or higher, you can run at least three showers at a time.
This includes places as far north as Boston, Philadelphia, Cleveland, and Salt Lake City.
Ground water temperatures of 62 degrees, can run three showers and a sink to boot! Or two showers and a couple other appliances.
This includes farther south areas like Memphis and Tulsa but also San Francisco!
For busy households where four showers may have to be run all at once, or 4 to 5 fixtures may have simultaneous use… the RTEX-36 says, as long as your ground water temperature is around 72 degrees Fahrenheit, I got you!
This, of course, applies to the likes of Miami, southern Texas and the Caribbean.
Pros
- Best GPM and the most powerful option
- One of the smallest in terms of depth
- Great tech from the Rheem brand
Cons
- One of the most expensive options
- One of the largest in height, width and is the heaviest model
8. BLACK + DECKER 36 kW Self-Modulating Electric Tankless Water Heater | Smallest in Height
Moving on to our final model which is from Black + Decker.
The Black + Decker 36 is another large option for your larger home.
Black + Decker claims it to be ideal for a 4-bedroom house and up to 8 simultaneous appliances.
This of course, depends on the fixtures, but it is very doable.
The cost of about $620 puts this model right around the middle of the pack. Definitely cheaper than some of its competitors.
Let’s dive further in to this one.
TECH SPECS
To start off, the dimensions are 4.5 x 14.75 x 23.25 inches (depth, height, width) which makes it one of the deepest and one of the widest… but it’s the shortest!
Good to note if height is your main area of concern.
If another area of concern is weight, it’s the second lightest option at 16.75 lbs.
It’s a 36-kW model, and of all the 36 kW options, it’s the lightest in weight.
Among all the 36 kW options, it’s also the second cheapest.
Though it’s maximum output of 7 GPM is the lowest of the four. But it’s higher than all the non-36 kW options.
REGIONAL INFO
In the colder regions where your ground water temperature is around 42 degrees Fahrenheit, the Black + Decker is still going to be able to achieve around 3.75 GPM.
Areas like St. Paul, Augusta, the Dakotas and all of Canada, this could mean you can run two showers at once depending on their individual GPM.
One shower and two bathroom sinks at once could definitely be a reality.
52-degree ground water temperatures can operate with 4.5 GPM.
That’s definitely two showers running at once and even a bathroom sink for places such as Baltimore, Indianapolis, Des Moines and Denver.
Going a bit farther south to places like Atlanta, Kansas City, and Santa Fe, the ground water temperature tends to be around 62 degrees.
You’ll get a nice 5.4 GPM and run two showers and another fixture or two with ease, perhaps even three simultaneous showers!
And that claim of the Black + Decker 36 being ideal for a 4-bedroom house and running up to 8 appliances simultaneously.
Areas where the ground water temperature is about 72 degrees Fahrenheit, this is you!
7 GPM, means three showers and another fixture, even including a low-flow shower can run at once.
If you have nothing but low-flow appliances… yeah you could run a few showers, a few sinks and a dishwasher on top of it all.
Miami, Hawaii, Puerto Rico and more… if you actually have to run 8 appliances at once, at least you know there’s an option for you.
And those facts perhaps make this model the best whole house electric tankless water heater in 2020!
Pros
- Great GPM and fairly powerful
- The smallest option in terms of height
- Of all 36 kW options, it’s the lightest and second cheapest
Cons
- Lowest GPM of all 36 kW options
- The largest option in terms of width and cubic inches
Best Whole House Electric Tankless Water Heater — Buyers Guide
As you can see, your options for an electric tankless water heater to serve your whole house are varied and plentiful.
It’s a lot of details to sift through, but that’s not a bad problem to have.
That just means we need to narrow down your needs and pinpoint the model that best suits what you’re looking for.
We have all the details to make that decision. Let’s put them to good use.
And this is where the information of your specific situation is going to come in handy.
Now that you’ve read how well these models operate in certain circumstances and have a better sense of them overall, we can figure out which ones will be best for you.
We’ll go through a list of frequently asked questions on this topic.
Some questions will encompass questions you have, some may be an exact match of questions that you have… and some may not be a match for you, but maybe for your friend or neighbor.
We might even uncover some questions you didn’t even realize that you needed answers to.
All in all, we’ll cover a lot here. And we’ll give a lot of answers.
This way we can finally find out what’s the best whole house electric tankless water heater in 2020 for you… and for everyone!
If I have a family of three and the most hot water we’d be running at once would be three showers, what’s the best whole house electric tankless water heater on a budget?
Let’s break this down by region.
If you live somewhere, where the groundwater temperature is around 77 degrees Fahrenheit (like Miami or Hawaii), the cheapest option on the list, the EcoSmart ECO 27 Electric Tankless Water Heater, can get that done.
It could even work in areas with groundwater temperatures of around 72 degrees (like Los Angeles or Orlando) as long as one shower is low-flow.
If your ground water temperature is around 72 degrees and you don’t want to go low-flow… then get the EcoSmart ECO 36 Electric Tankless Water Heater.
And even if you’re in areas with 62-degree groundwater temperature (Charleston, Atlanta, Oklahoma City), this option is the cheapest available to get the job done.
Moving to the likes of areas with ground water temperatures of 52 degrees (New York City, Chicago, Seattle), the ECO 36 could get it done if you incorporate a low-flow option, but with the Rheem RTEX-36 Tankless Water Heater you wouldn’t have to.
Anywhere colder (Much of Minnesota, Alaska, Canada, etc.), the Rheem RTEX-36 Tankless Water Heater is going to be your best bet, but you will likely need at least one low-flow option in there.
Living in Canada, if my spouse and kid tend to get ready and shower at the same time in the mornings and I typically will only use a bathroom sink at that time, what would be the best whole house electric tankless water heater for us?
I would choose either the Stiebel Eltron Tempra Plus 36 kW Tankless Water Heater or the Rheem RTEX-36 Tankless Water Heater.
The RTEX-36 is a little less expensive, however, the Tempra Plus line ensures you won’t ever have cold water surprises. If the demand gets a little too high, it just lessens the flow of water.
If you’re trying to save a bit of money or have a low-flow sink, the RTEX-36 might be a better choice.
But if none of your appliances are low-flow and you don’t want to take any chances, the Tempra Plus 36 is well worth the price.
What’s the cheapest whole house electric tankless water heater in 2021?
The cheapest model on this list is the EcoSmart ECO 27 Electric Tankless Water Heater.
What’s the absolute best whole house electric tankless water heater in 2021?
I would put my money on the Rheem RTEX-36 Tankless Water Heater as it’s the most powerful and seems very well-rounded.
For a family of four, what’s the best whole house electric tankless water heater?
This will depend on your usage and your region.
In the scenario of, every person in the household could be showering at once, you’ll likely just want to get the Rheem RTEX-36 Tankless Water Heater or the EcoSmart ECO 36 Electric Tankless Water Heater.
If you live in the southern United States, you could achieve this with any type of showerhead.
For most other regions, you’ll need one or two low-flow showerheads. Far north like Canada, they may need to all be low-flow.
And if all your showerheads are low-flow, and you’re looking to save some money, the Black + Decker 36 and EcoSmart ECO 36 Electric Tankless Water Heater are the cheaper options to get this done.
Now, if the scenario is more like, a two-bathroom household that never has more than two showers running at once, but may have another two appliances running… colder regions will want to stick with one of the 36 kW options mentioned above.
And even the Stiebel Eltron Tempra Plus 36 kW Tankless Water Heater as well.
If you’re in a warmer climate, like Florida, southern California, southern Texas, etc. you could get away with this type of hot water usage with an EcoSmart ECO 27 Electric Tankless Water Heater or a Rheem RTEX-27 Tankless Water Heater.
What’s the best whole house electric tankless water heater in 2021 if I want the smallest option to operate a two-bathroom situation?
Let’s break it down by region again.
Up north with groundwater temperature around 42 in areas like Canada, Minnesota, The Dakotas, Maine… the smallest in depth would be the Rheem RTEX-36.
The smallest in height would be the BLACK + DECKER 36.
The smallest in width would be the Stiebel Eltron Tempra Plus 36.
The smallest in cubic inches would be the Stiebel Eltron Tempra Plus 36 as well.
The above also goes for places with groundwater temperatures of around 52.
The only difference is, if you’re talking about the smallest in height or cubic inches, you could also now consider the Stiebel Eltron Tempra Plus 29, which is less powerful than the 36 but the same size.
Areas with groundwater temperature of around 62, once again, same answers as above, however, now the absolute smallest in cubic inches can be brought into play, the EcoSmart ECO 27.
And the Rheem RTEX-27 can get the job done here has the same shallow depth as the Rheem RTEX-36, but cheaper.
And areas with groundwater temperature of around 72, again, look above to all the same answers.
Now, the Rheem RTEX-24 can also get the job done, and has the same shallow depth as the other two models from Rheem, and is the cheapest of all the three Rheem models.
If I have all low-flow appliances and a family of four that all gets ready at the same time, what’s the cheapest whole house electric tankless water heater in 2021?
If you live in areas where the ground water temperature is 42 and basically all the way up to about 60… the cheapest will be the EcoSmart ECO 36.
If you live anywhere where the groundwater temperature is higher than 60, then you can go with the EcoSmart ECO 27.
If I have all low-flow appliances and a family of three that all gets ready at the same time, what’s the cheapest whole house electric tankless water heater in 2021?
Similar to the above question, if you live in an area where the groundwater temperature is around 42, best to go with the EcoSmart ECO 36.
Unless if it’s only going to be two showers and a bathroom sink that are running at a time, then you could get away with the EcoSmart ECO 27.
And everywhere else in North America… EcoSmart ECO 27 has you covered.
Best Whole House Electric Tankless Water Heater — Conclusion
There you have it! There’s no one great answer for everyone, but there is a great answer somewhere in this article for anyone.
The most important things for you to think of when making your purchase for an electric tankless water heater includes:
1) Your region and the average ground water temperature.
2) How many people are in your household.
3) How many appliances may be run at once.
Of course, you may also want to factor in budget and perhaps extra nice features that models may have.
Size of the models plays a part for many people as well.
What’s great is that there is definitely an option for you on my suggested list.
No matter what your grocery list includes, there are options that will check off all your boxes.
The details are all there! You’re ready.
Go ahead and make your decision on the best whole house electric tankless water heater in 2021!
