The 10 Best Tankless Electric Water Heater in September 2023

On demand a continuous and unlimited supply of hot water

Sleek design saves space and no venting required

Requires hard-wired 240 or 208-volt electric service, with a maximum draw of 28,800 watts at 240 volts or 21,600 watts at 208 volts

Requires 3 separate dedicated 40 amp breakers with 8 gauge copper wiring, and a minimum of 200 amp total service to the residence

Lifetime warranty

Save up to 60-percent on your water heating cost with an ECOSMART electric tankless water heater

Never run out of hot water with an ECOSMART tankless water heater

Patented Self Modulating Technology and design.Activation flow 0.3 GPM

ECOSMART tankless water heaters are 99.8-percent energy efficient

100 A

Endless on-Demand Hot Water; Consistent hot water when you need it that never runs out; Continuously monitored water temperature and controlled flow rates ensure efficiency and consistent performance within 1 degree of selected temperature

Save Space; EcoSmart tankless electric water heaters are 90% smaller than traditional tank heaters; may be installed on wall or at point of use; Dimensions 17 x 17 x 3.75 inches 

Save Energy; EcoSmart tankless electric water heaters are 99% thermal energy efficient; Only heats water when called unlike a tank heater that maintains water temperature even when not being used. Save up to 50% in water heating costs according to the Department of Energy

EcoSmart ECO 27 Sizing; Refer to the sizing map. Requires 3x40 AMP Double Pole Breaker, 27-kilowatt tankless electric water heater ideal for providing hot water for whole home applications; provides between 2.7 and 6.5 gallons-per-minute depending on the inlet water temperature; refer to the sizing guide to select the proper solution

Warranty and Certifications; Limited Lifetime Warranty on electronics, exchanger and element; UL-499 certified; ETL Listed

Required Breaker Quantity: Three 40 Amp Double Pole

Recommended Electrical Panel: 200 Amps

NEVER run out of hot water with an ECOSMART tankless water heater.

Save up to 12 cubic feet of storage space.

Digital temperature control in 1-degree increments gives users complete control of hot water

External digital thermostatic control with LED display (+/1 degree accuracy)

Most advanced self-modulation, adjust power to meet hot water demand

Durable Copper immersion two heating elements, field Serviceable. Flow Rate- up to 4.4 GPM

Simple installation – bottom 3/4 inch NPT water connections

Threaded for easy replacement, simple installation, digital temperature display

Endless On-Demand Hot Water; Consistent hot water when you need it that never runs out; Continuously monitored water temperature and controlled flow rates ensure efficiency and consistent performance within 1 degree of selected temperature

Save Space; EcoSmart tankless electric water heaters are 90% smaller than traditional tank heaters; may be installed on wall or at point of use; Dimensions 11.5 x 8 x 3.75 inches

Save Energy; EcoSmart tankless electric water heaters are 99% thermal energy efficient; Only heats water when called unlike a tank heater that maintains water temperature even when not being used.

EcoSmart ECO 11 Sizing; 13-kilowatt tankless electric water heater ideal for providing hot water for a bathroom, small sink, office breakroom and other point-of-use or low-flow applications; provides between 1.3 and 3.1 gallons-per-minute depending on the inlet water temperature; refer to the sizing guide to select the proper solution

External adjustable digital thermostatic control with LED display (+/1 degree accuracy

Durable Copper immersion two heating elements, field Serviceable.Self-modulating power control

Simple installation – 1/2 NPT adapters included; side 1/2 inch Compression water connections

99.8% energy efficient. External controls to adjust temperature in increments of 1°f. Water-Saver Shower Head – 1.5 GPM

Threaded for easy replacement, simple installation, digital temperature display 54 A. 13kW Model Flow Rate: up to 3.17 GPM

54 A

ON/OFF Dial Control with adjustable digital temperature display

Self-modulating power control

24kW Model Flow Rate: up to 5.9 GPM for RTEX-24

Bottom 3/4" NPT water connections

On demand, consistent and continuous hot water

The product is highly durable

The product is easy to use

Manufactured in China

Heating elements are durable and are threaded for easy replacement

Activation Flow - 0.3 GPM

Sleek and compact design with digital output temperature display

ECOSMART tankless water heaters are 99.8-percent energy efficient

Manufactured in United States

Pipe Fittings:3/4 inch NPT

Required Breaker:4 x 40 A

150 A

☼ Endless Hot Water: Imagine you are the last one in your family to take a shower before heading out for the day. You turn on the faucet and the water is freezing cold. Too bad you don’t have an Airthereal Electric Tankless Water to provide endless hot water on demand with no preheating, temperature fluctuations, or running out of hot water in the tank.

☼ Save Space: That water heater in the basement or utility closet takes up a ton of space. This wall-mounted water heater uses 90% less space than a traditional hot water heater with a tank.

☼ Save Energy: Water is only heated when you need it, not stored in a hot water tank. The self-modulating temperature technology only uses energy to heat up water while you are using it to save up to 50% on water heating costs compared to a typical tank water heater.

☼ Important Note: In order to install 18kW Electric Tankless Water Heater it requires 240 Voltage, 2 x 40 AMP Circuit Breaker Size and a set of 2 x (8AWG/2) wires. Please check to confirm that your breaker panel meet these specifications.

☼ Safe To Use: With high temp protection, dry heating protection, and electrical leakage protection you can rest easily knowing you have safe, on-demand hot water to use on your schedule. The electric and fluid systems are completely separated to prevent electric leakage and water pipe corrosion.