8 Best 18 kW Electric Tankless Water Heaters Reviews

When you require a continuous flow of hot water at home, there is a need for checking out for efficient and robust water heater. They are highly skilled since they will be assuring you of convenient and reliable water heating. Their control and usage are smooth as a result of their present LCD control panels. Besides, the water heaters will be safe for use. There are a variety of water heating systems from which you may choose the convenient services. In this review, you will have a look at the best 18kw electric tankless water heaters. Read through this review and purchase the product that is pleasing you most.

What Is the Best 18 kW Electric Tankless Water Heater that Worth Buying?

Quick Pick From the Best 18 KW Electric Tankless Water Heaters Comparison Chart

Photo Title Price Buy
EcoSmart ECO 18...image Ecosmart ECO 18 Electric Tankless Water Heater $361.62 Check Latest Price
Rheem 18kW 240V...image Rheem 240V 2 Heating Chambers RTEX-18 Residential Tankless Water Heater Check Latest Price
CAMPLUX Tankless Electric...image Camplux Electric Tankless Water Heater, TE18 Household Point-of-Use Water Heater Check Latest Price
Thermoflow 18KW at...image Thermoflow Electric Tankless Water Heater, 18kW at 240 Volts Instant Hot Water Heater Check Latest Price
Atmor ABC (16Kw) Atmor AT-910-18TP ThermoPro 18 kW / 240V 3.7 GPM Digital Thermostatic Tankless Electric Instant Water Heater Check Latest Price
BLACK+DECKER Tankless Electric...image BLACK + DECKER Black and Decker 18 kW 3.7 GPM Electric Tankless Water Heater Check Latest Price
Marey ECO180 Electric...image Marey ECO180 18kW 4.4 gpm 220V Self-Modulating Multiple Points Tankless Electric Water Heater for The Whole US Territory $310.86 Check Latest Price
iHeat Tankless AHS18-D...image iHeat Tankless AHS18-D 240V 75A 18KW Stainless Steel Enclosure $479.00 Check Latest Price

Usages Of 18 Kw Electric Heater

For houses using 41 gallons or even less of hot water daily, demanding an 18 kW electric tankless water heater will be 24% to even 34% much more energy-efficient than the use of tank water heaters with conventional storage. They will be 8% to 14% more efficient for use in homes using a lot of hot water to even 86 gallons every day.

18kw heater

Is 18 Kw Electric Tankless Water Heater Suitable For Multiple Showers

The 18 kw is a mid-range electric tankless water heater bearing self-modulating and EcoSmart’s technology. It has the capability of heating two showers and two sinks simultaneously while in warm climates. Besides, it can heat one tub and one shower in the case of colder climates.

Top 8 Best 18kw Electric Tankless Water Heaters Reviews

1. Ecosmart ECO 18 Electric Tankless Water Heater

18kw in amps

A water heater is known for the provision of long term services. As a result, most people are preferring purchasing it as it assists in the provision of durable services. The usage of the water heater is a straightforward process. As a result, you will use it with ease without requiring the help of other people.

The manufacturer of the product has made use of the stainless and copper components. The materials play a significant role in ensuring that the item ends up lasting for a long duration of time. The water heater will assist you in saving to even 60% of the costs on water heating using the self-modulating and most advanced technology present.

With this tank, you have the surety that there is no single time in which you will end up running out of hot water. You will also save a lot of space to even 12 cubic feet on your storage space. The digital temperature is controlling an increment of one degree, thus giving the users complete control of the present hot water.

  • Highly durable
  • Easy to use
  • Save on space
  • 60% reduction in electric consumption
  • Stylish, light weighted and compact
  • Not very hot for bathtub use

2. RTEX-18 Residential Tankless Water Heater

18kw tankless water heater

RTEX is an energy-efficient and pro classic electric tankless water heater. It is providing continuous and endless hot water for use in single utilization points such as bathrooms, sinks, and showers. The water may as well be used in a variety of other various applications. It has the capability of providing instant and endless energy, which is efficient for use in a maximum of two bathrooms.

The tank is also excellent as it has mobile homes, travel trailers, campers, and RVs. RTEX-18 has two heating elements that are engrossed using durable copper. Therefore, you have the surety that the product is going to last you for an extended period.

The tank is also featuring external digital thermostatic control which is accompanying a LED display. The thermostatic control will ensure you end up acquiring unlimited hot water. Rather than the simple installation, RTEX-18 has been promising in the provision of a simple replacement and more comfortable use.

  • Easy to install
  • Compact allowing for extended usage
  • Easy setting of temperatures
  • Flickering of its bulb lights after heater connection

3. Camplux Electric Tankless Water Heater

18kw electric heater

Camplux tankless water heater is highly portable. You will have the chance to travel with the unit as you wish. Therefore, you will end up acquiring water to any point that you want to. Additionally, it has a convenient handle as a result of its compact designs. Setting up is very easy as the overall weight of the unit is below 11 lbs.

More also, it has low energy efficiency as you will require only 2 PSI to complete the activation process. While in a place with low inlet flow, the unit will be working fine in the absence of any kind of hindrances.

As regards the gas chamber, you will require a minimum of 0.4 PSI to succeed in the operation of the propane unit. You will also be needing a water supply of 12-volt for use in the process of the tankless heater. In the case where the supply pump is absent, you will be operating the unit using 2D cell batteries. The water heater will be providing 1.32 Gallons every minute. It is not sufficient to assist in the provision of hot water for an extended period.

  • Easy installation
  • Comes with equipment’s for unit installation
  • Has low energy requirements
  • Operated in the absence of electricity
  • Has a low water flow rate

4. Thermoflow Electric Tankless Water Heater

ecosmart 18kw tankless water heater

The heater is guaranteeing you at low costs. As a result, you will be saving on the amount of money that you would spend buying an equally similar product. Besides, it is known for saving energy. You will thus end up saving on the amount of money you would spend on the use of a product using more amount of energy. It provides great amounts of energy that are endless.

Therefore, it is perfect for use in your house as they are no single time in which you will end up running out of energy. The temperature technology is self-modulating.

The water heater tank has a compact and stylish design which is allowing it to be installed in any place near hot water taps. It is thus taking up less space, which is considerable, allowing the saving of the existing living space. More also, it is dedicated to the provision of endless hot water that is in high demand. Electric temperature control is exclusive. It is thus ensuring there is a steady output of temperatures even while the flow rates will be varying both up and down.

  • Hot water flow is limitless
  • Environmentally friendly
  • Pro-energy savings
  • Has assembly issues

5. Atmor AT-910-18TP Thermostatic Tankless Water Heater

18kw electric heater

Atmor tankless water heater is revolutionizing the heating of water using self-modulating technology. It is providing unlimited hot water when it is in need without having to wait. The advanced technology is regulating the required amount of energy to help in the heating of water. It is thus delivering significant savings on given energy bills and lowering on water consumption.

The digital panel is easy to use, allowing full control with given power. It is thus making temperature adjustments on the exact degree for appropriate water temperature all the time.

The unit has been certified by IP54, thus keeping the internal components dry and safe. Corrosion-resistant and durable stainless steel is allowing for a longer life expectancy and heating efficiency. It is perfect for use in both moderate and warm climates. Rather than using heating water present a large storage tank, the tankless water heater will be activating after sensing of water flow and shuts off after the stoppage.

  • Durable
  • Easy to maintain
  • Easy to use
  • No need of venting
  • Requires a high amount of temperatures

6. Black and Decker 18 Kw 3.7 GPM Electric Tankless Water Heater

18kw tankless water heater

Black and decker heater that is dedicated to offering large amounts of hot water. Therefore, you will not have to worry m on the possibility of having to wait or evening running out of water. Contrary to the tank water heaters that are conventional, you will stop consuming a lot of energy as your water remains hot throughout the time. Digital technology will also play a significant role in reducing energy consumption and saving money on your energy costs through the heating of water, which is on-demand.

The unit will not be requiring any venting or gas lines. The compact design is allowing the process of installation to be taking place in any place. The procedure may take place in the basement, garage, closet, and in the cabinet. You will have the surety of earning precious space through the installation of water heaters.

Besides, it is offering exceptional value since it is known for having a long period of warranty that lasts for seven years. The selection of the best water heater will depend on the incoming flow rate, water temperature, and the output temperature that is desired.

  • Easy installation
  • Saves on costs incurred in heating water
  • Durable
  • Expenses on additional installation

7. Marey ECO180 18Kw Tankless Electric Water Heater

ecosmart 18kw tankless water heater

The tankless water heater is providing a power of 18Kw. It is thus perfect for use in many parts all over the world. The unit is providing 31 degrees F, which is increasing at 4.4 GPM. You will, therefore, end up having a variety of points for use while running in the hot climates simultaneously. While living in colder regions, the unit will end up reaching 80 degrees F while at 1.5GPM for the output of hot water at one single point for use at one time.

The unit is usually installed to even more than 40 Ft from the point that is intended for use. Installation ought to be done professionally since the electrical requirements are demanding 50 Amp breakers.

Additionally, there is no necessity of preheating ECO180 since it is providing hot water instantly on-demand. Activation is done by the use of water pressure from the instance in which there is the opening of faucet. The ECO line of Marey is complete as it has been designed using heating elements that are corrosion resistant. It will thus end up reducing the hard water that is building up from either calcium or chlorine. The tankless water heater is saving on energy since they are using up less energy of 60% than the traditional tank water heaters. Therefore, they are environmentally friendly and cost-effective.

  • Less water pressure required
  • Avoids wastage on temperatures
  • Saves on space
  • Installation is difficult

8. iHeat Tankless 18KW Electric Water Heater

ecosmart 18kw tankless water heater

Iheat electric water heater that has been known for an extended period as a result of its reliability and durability. It has sufficient power for use in heating water for use in average-sized homes. The tank is in use both in cold and moderate climates. Besides, it is packing a wallop bearing an electrical draw with 18 kilowatts.

Its temperature is rising to even 122.4 degrees F while at 1GPM and to even 61.2 degrees F while at 2 GPM. You will end up determining how the tankless water heater will be performing in extreme climates and applications. You will use the product in two-bath homes in the case where the incoming water temperature is more than 55 degrees F.

  • Saves on heating cost
  • Save on space
  • All-time supply of hot water
  • No necessity for tank use
  • Requires work to setup


You now have the best tankless water heater that will be assuring you of acquiring hot water whenever you will require it. The water heaters are powerful as a result of their high heating system. They are thus providing hot water continuously as long as you need it. Besides, they are efficient and highly durable, designed using the best materials.

They are thus delivering performance in the long term to meet your expectations. Their usage and control are easy. The easy in usage is as a result of its LCD control panels. Therefore, you will be adjusting the temperatures to the heating system which you require. As a result of the compact and sleek design, the water heaters are highly ideal for usage even in smaller spaces, thus useful for all users.

Top 3 Best 18kw Electric Tankless Water Heaters


David: Penn State-educated Mechanical Engineer and Business-savvy Fluid Dynamics Specialist. Balances family plumbing business support with a thriving engineering career at a top, undisclosed company. (they want it that way) I help Will with plumbing and HVAC needs on his Real Estate.

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