I Tested And Reviewed 8 Best Whole House Electric Tankless Water Heater (2023)

I received the item and upon unboxing, I was disappointed to find that the case face was damaged and three out of four machine screws that are supposed to hold the heating element down were loose and rattling around inside. This initial experience left me unimpressed with the product.

It seems that the machine screws may have worked themselves out due to the weight of the heating element and possibly rough handling after manufacture. One of the screws even stripped altogether, causing further inconvenience. I suggested to the sellers that each bracket should have a clip nut in addition to relying on the bracket alone to hold such a heavy component. Although a replacement front cover was not available, I did receive a $20 goodwill refund from the sellers.

Despite these initial issues, I decided to hook up the unit and found that it actually works quite well. However, the thermostat appears to be a bit off, reading about 10 degrees higher than the actual water temperature at the tap. I have yet to fully explore if this is an over-reading or calibration issue. In order to determine if any temperature loss occurs between the heater and the tap, I would need to disconnect the hot side, which I am unsure if I will do.

Furthermore, I discovered that the unit is incapable of delivering more than 1.5gpm, even though the manufacturer's product information and manual claim a theoretical 1.8gpm. While this is sufficient for hand washing, I doubt it would be suitable for showering. If anyone has the same unit and is experiencing better performance, please feel free to share your experience in the comments.

Update: Unfortunately, the unit has now failed with an E2 error code. This error code appears as soon as power is applied to the unit after resetting via the circuit breaker. I have only been able to clear the code and resume heating once by resetting the breaker, but the unit shuts off with the same error code after less than a minute of operation. I am currently waiting to hear back from the seller, although I am not optimistic given that the unit is out of warranty by three months and there have been reported issues with customer service according to other reviewers.

I have tested multiple water heaters, but this particular one stands out as the best in terms of providing hot water for my shower. Even with my well's input water temperature at a solid 56F, this 7kw water heater manages to raise the water temperature to 120F without any flow restriction in the showerhead. With a 2.5 gpm flow restrictor, it reaches the maximum temperature of 131F. I am impressed by the consistency of the water temperature at the showerhead, as there are no fluctuations even when my well pump cycles on or off, which was an issue with other water heaters I've used.

The package includes an input flow restrictor valve, which I installed but left open for full flow. I appreciate the fact that I can easily see the water temperature on this unit. Installation was a breeze, as I was replacing a previous water heater. It fits perfectly under my bathroom sink without taking up much space, and the wall bracket and screws are included for mounting.

The only downside is that the instruction manual is a bit lacking in content, but I personally didn't need it for installation. Overall, I am extremely satisfied with this unit and will be purchasing another one for my second bathroom. It is an excellent deal.

I selected this particular water heater because it had the highest rating for gallons per hour and was compatible with the existing wiring from my old tank water heater. Despite my shower being quite far from the heater, it still works well once all the cold water has been purged from the line. It provides unlimited showers for one person and can also handle a kitchen sink. However, it may not be large enough to replace a standard tank heater, and the 220v power requirement may be inconvenient for under sink use. So far, it has been working perfectly fine, and I have set it to 114F, resulting in a water temperature of around 103F at the tap.

Unfortunately, I am unable to provide a review for this water heater as I have not been able to power it on. Additionally, the product did not include an installation manual, which was disappointing. However, after seeking assistance from an electrician, we managed to figure out the European color-coded wiring system and successfully installed it. Since then, it has been working great.

Compared to another water heater that only provides a trickle of hot water, this one is capable of producing enough hot water for a satisfying shower. It may even be suitable as the sole hot water heater for a house, although I am still considering this option.

I replaced my 40-gallon hot water tank with this instant heater in my cabin in the woods, and I couldn't be happier with the results. Not only does it save me space, but it also provides enough hot water flow to take a shower and do dishes, even in winter when temperatures drop to -20 degrees Celsius. The installation process was incredibly easy, and I had it up and running in no time.

One thing that impressed me about this instant heater is its performance. Despite its small size, it packs a powerful punch and has intelligent processing capabilities that ensure efficient water heating. I no longer have to worry about running out of hot water or waiting for the tank to refill.

I also want to commend the seller for their exceptional customer service. When I encountered an issue with the initial unit, they promptly contacted me and sent a replacement for free without me even having to ask. It's refreshing to come across a responsible and reliable seller who values their customers and fulfills their commitments. I highly recommend purchasing from them.

Lastly, I would like to mention that this instant heater is perfect for kitchen sinks. However, it is advisable to install a pressure reducer to regulate the water flow and prevent any potential damage.

I recently installed the Stiebel Eltron Tempra 29 Plus hot water heater and I am extremely satisfied with its performance. I tested it at 110F degrees and it was able to handle running two showers and three faucets simultaneously with hot water. I also tested it at 115F degrees and found the temperature to be as hot as I would want to touch. Even with the increased temperature, there was no reduction in water flow. This compact unit is truly impressive.

In terms of installation, I purchased the unit in September 2017 and decided to install it myself. The plumbing materials cost me around $100 and it took me approximately 5 hours to complete. For the electrical work, I hired an electrician who installed three 40 Amp breakers in my box (the device has a maximum draw of 120 Amps) in about 3 hours. The electrical work cost me around $300. Overall, the installation process was straightforward and hassle-free.

Since installing the Stiebel Eltron Tempra 29 Plus, it has been working flawlessly. Even when we push the limits by running multiple hot water sources simultaneously, there is only a slight pressure drop as the unit adjusts to compensate. This is not a concern for me as we have a well with a maximum pressure of 50psi. I have noticed a minor power dip when the hot water engages, but it is not significant enough to be worrisome. However, it might be more noticeable if you are using incandescent lights instead of LED lights.

Long-term savings were one of the factors that influenced my decision to purchase this unit. With a damp basement, a traditional tank water heater would typically last only around 5 years. In contrast, with proper care, the Stiebel Eltron Tempra 29 Plus should last for decades. This durability gives me peace of mind and the expectation of significant savings in the long run.

Now, after using the Stiebel Eltron Tempra 29 Plus for over a year, I have discovered some tips to maximize its efficiency and savings. Firstly, if you have a faucet that mixes hot and cold water, it is recommended to replace it with separate hot and cold knobs. This is because the Stiebel Eltron Tempra 29 Plus does not distinguish between a small amount of hot water and fully opened hot water. By always running just cold water when it is not needed, you can avoid engaging the hot water unnecessarily and save on electricity costs. Additionally, comparing your water bill rate to your electric bill rate, you may find that running an extra couple of gallons of water is far less expensive than the electricity used to heat it. To minimize the time needed to fill your sinks, consider removing the aerator from your taps, as it is designed for conventional hot water heaters and conserves water that would otherwise be wasted. Removing the aerator maximizes water flow, reducing the time the heater needs to operate and therefore lowering your electricity consumption.

By following these simple steps, my overall electric use has been reduced by about a third compared to the same period last year when I had the aerators on and single faucet systems in place. These small adjustments have resulted in noticeable savings on my electric bill.

One last observation I would like to mention is that although the instructions advise against freezing, we experienced a couple of heating issues during the winter in Maine and our unit froze a few times. Surprisingly, the system emerged from the deep freeze without any noticeable problems. While I do not recommend freezing your pipes intentionally, it is reassuring to know that the Stiebel Eltron Tempra 29 Plus is capable of handling such situations.

I recently installed the EcoSmart 24KW heater as a backup for my solar water heater, and I must say, I am extremely satisfied with its performance. The installation process was relatively straightforward, although I did have to make a few adjustments to ensure optimal functionality.

To begin with, I ran two 3/4" EMT conduits and used 3 pairs of #8 copper wires for the installation. The EMT served as the safety ground, providing an added layer of protection. However, I did encounter some vibration issues initially, as the wires vibrated at 60Hz due to magnetic forces while the heater was running. To rectify this, I had to switch to using 4 and 2 wires in each conduit, which effectively eliminated the vibration problem.

In terms of heating efficiency, the EcoSmart 24KW exceeded my expectations. Even on cold and cloudy days when my solar system wasn't generating much heat, the heater managed to bring the water up to 120 degrees F without any issues. I have a 3.3 gal/minute shower head, and the heater coped well with a 65-degree input water temperature.

I did discover a helpful tip regarding adjusting the shower temperature. It's better to use only the cold water to regulate the temperature, rather than adjusting both hot and cold. This ensures a consistent flow rate through the EcoSmart without creating any feedback loops that may affect the temperature control. Once I learned this, the system worked flawlessly.

During the installation process, I had to drill two additional holes in the bottom of the EcoSmart to accommodate my EMT connectors. Unfortunately, the included hole/wire-clamp didn't work for me, but using a step drill from Harbor Freight solved the problem easily. I used two corrugated copper tubes for the water connections, and tightening them was a breeze, as the copper tubes only required one turn past hand-tight. I used an 1-1/8" wrench, although a crescent-style wrench couldn't fit due to space constraints.

One factor worth mentioning is that the EcoSmart water heater may disqualify you from certain photovoltaic subsidies offered by your city. In my case, the city required a solar water heater that preheats water for a 30 amp tank water heater and mandates the use of a water heater timer to minimize peak electric load during the afternoon. While the EcoSmart is not compatible with this program, it's important to consider your specific subsidy requirements before making a purchase.

In terms of power requirements, I opted for the 24KW model instead of the 27KW to ensure it wouldn't overload my 200 Amp main breaker. With a heat pump heater with 60 Amp electric strip coil backup heat, I wanted to avoid any potential issues. The 24KW model turned out to be the perfect fit for my needs, providing ample heating capacity without risking any electrical complications.

Finally, I must mention the positive impact the EcoSmart has had on my electric bill. Last month, my bill came in at a mere $52, the lowest it has ever been for my all-electric home. This significant reduction in energy consumption is a testament to the efficiency and effectiveness of the EcoSmart 24KW.

All in all, I am extremely pleased with the EcoSmart 24KW heater. Its performance has surpassed my expectations, and the installation process, while requiring a few adjustments, was relatively straightforward. Considering its energy-saving capabilities and overall effectiveness, I confidently give it a 5-star rating.

I recently purchased this water heater and I must say, it performs exactly as expected. It heats up quickly and effectively, providing a never-ending supply of hot water. However, there are a few things that potential buyers should be aware of before making a purchase.

Firstly, this water heater requires two electrical circuits instead of the standard one. This means that it may not be a direct swap for your old water heater and additional electrical work may be needed. It is important to do your homework and determine the requirements for power installation.

The water heater utilizes two 2 pole 50A breakers, which is a higher amperage compared to most standard electric water heaters. This may require the installation of new circuits and possibly the assistance of a contractor, adding to the overall cost of installation.

Despite these considerations, the water heater is definitely worth it for its space-saving design, continuous hot water supply, and lower utility bills. Once the necessary modifications are made, installation is a breeze. In my case, I already had a 240v sub panel with a single 50amp dual pole breaker that fed my dryer, so I only needed to purchase a 6 space box, 3 50amp dual pole breakers, and 8 feet of 8-3 wire.

The actual installation process took me around 20 minutes to complete. As soon as the water was turned on, the heater sprang to life, providing steaming hot water in less than 15 seconds to a kitchen faucet 15 feet away. The unit works flawlessly, even with multiple sinks and showers running simultaneously.

Living in mid-Florida where the ground water temperature is consistently 72 degrees, this water heater easily produces extremely hot water for multiple fixtures. With the temperature set at 125 degrees, I can run the cold water at full flow and simply add half hot water in the shower for the perfect temperature.

In the four weeks since installation, I couldn't be happier with this water heater. It has exceeded my expectations and I hope it continues to perform well in the long run, despite some negative reviews suggesting otherwise. So far, those reviews have been proven wrong and I remain optimistic about the durability of this product.

After using this tankless water heater for a month, I can confidently say that it outperforms the gas tank style unit I had before. Unlike the previous unit, which ran non-stop, this one is more efficient. I believe that there would be better reviews for this product if people took the time to do their own research before purchasing. It's surprising how many negative reviews are based on user ignorance rather than actual product performance.

As of now, I am extremely satisfied with this tankless water heater and anticipate seeing energy savings reflected on my utility bill soon. While it does draw 150 amps at full capacity, as an electrician, I have tested it and discovered that the 4 circuits are actually staged. Unless you have multiple people showering simultaneously, you will likely never experience that level of current draw.

I will revisit this review after a year to reassess, but for now, I give it 5 stars.

Before purchasing this tankless water heater, I read various reviews on other Ecosmart models. Some were positive, while others mentioned receiving used or defective units and having poor customer service experiences. I am pleased to report that the unit I received was brand new, and Ecosmart's customer service promptly responded to my installation inquiry.

To assist in your decision-making process, I will provide three parts in my review: (1) considerations before buying this type of system, (2) my impressions of this specific unit, and (3) a simple calculation to determine the appropriate size unit for your home if you decide to go tankless.

I have also included a video overview of the unit, showcasing its appearance and internal construction, along with a supplementary table of numbers for reference.

The water heater is a great choice for small studio apartments, capable of powering a shower, bathroom sink, and a kitchen sink. However, there are a few things to keep in mind.

Firstly, some users have experienced issues with water temperature when the shower is turned on. This can be resolved by adjusting the output valve to about half or using a flow limiter. It's important to note that the 8w unit may struggle to heat water for multiple fixtures simultaneously, so if you require more than just a sink, opting for a slightly larger unit is recommended.

On a positive note, this water heater is a reliable replacement for other models, such as the RTE 9, which has been working fine for over 6 years. The installation process is straightforward, requiring only three connections and basic electrical knowledge. The inclusion of SharkBite push-to-connect plumbing connectors simplifies the installation further.

For those living in small spaces, this tankless water heater is suitable as a whole-house solution. It offers adjustable water temperature, providing comfort during showers and everyday use. Despite concerns about potential clogging, many users have found this water heater to be reliable.