The 10 Best Tankless Hot Water Heater in 2024

☼ Instant Hot Water: The 8kW electric tankless water heater supplies instant & endless hot water of 108℉ or higher with no waiting for preheating or temperature fluctuations. perfect companion for faucet and sinks, bringing you perfect experience of comfort and relaxing.

☼ 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 energy compared to a typical tank water heater.

☼ Save Space: A traditional 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 hot water heater with a tank. Compared to our next-largest 9kW water heater, this 8kW unit is 30% smaller with only 3,412 BTUs.

☼ Important Note: In order to install 8kW Electric Tankless Water Heater, it will require a 240 Voltage, 40 AMP circuit breaker. Please check to confirm that your breaker panel meets these specifications before purchasing.

☼ Safe To Use: With high temp protection, dry heating protection, and electrical leakage protection you can rest easy 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.

Endless Hot Water: Enjoy unlimited hot water flow throughout the house; compact, durable, and easy to install; professional installation recommended

Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary

Optimal Water Pressure: High-performance up to 5.3 GPM hot water flow rate for a powerful, constant stream

Enhanced scale detection lessens possibility of serious, long-term damage to unit

Guaranteed to Last: 10-, 5-, and 1-year residential factory warranty for heat exchanger, labor, and parts, respectively

CONTINUOUS FLOW – Advanced Flow Control patented technology invented by Stiebel Eltron, automatically maintains water temperature for constant comfort. It’ll reduce flow slightly if hot water demand exceeds capacity. Hot showers will never be interrupted again

SPACE & ENERGY SAVER – Its small, sleek white design saves space yet still provides endless hot water for your whole house, and no venting is required. Eco friendly unit saves energy with auto-modulation and the ability to electronically control water flow. Savings monitor even shows how much you save on energy costs

EASY OPERATION – Electronic switch activates the hot water heater and it’s noise free while in use. Has a digital temperature display and preset temperature and memory buttons, while the interior solid copper heating system does all the power work

TEMPRA 24 PLUS – This specific model is 24kW, 240V, requires a min recommended electric service of 150 A, and offers an output water temperature of 68° to 140°F. Check our guides below to compare features of our various Trend and Plus models, each available in different kW levels

WARRANTIES INCLUDED – Stiebel Eltron’s top-rated electric tankless water heaters perform with the highest standards for comfort and reliability. Our 7-Year Leakage and 3-Year Parts Warranties are included with purchase

Endless Hot Water: Enjoy unlimited hot water flow throughout the house; compact, durable, and easy to install; professional installation recommended

Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary

Optimal Water Pressure: Up to 7 GPM hot water flow rate for a powerful, constant stream

Instant Heating: Equipped with Circ-Logic - Pair with an external pump to reduce wait time for hot water via scheduled or on-demand recirculation

Guaranteed to Last: 15-, 5-, and 1-year residential for heat exchanger, labor, and parts, respectively. Wifi monitoring.

The product is highly durable

The product is easy to use

Manufactured in China

Amperage (amps): 75. Activation flow: 0. 3 GPM. Flow Rate @ 35 F Rise (gallons/min): 3. 51 gal (US)/min

The product works and is compatible with 2 X 40 AMP (DP) breakers and 2 X 8 AWG wire

Lifetime warranty for residential use

Save up to 60% on your water heating costs with the most advanced, self modulating technology available

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

75 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

☼ 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.

Original Design: Tankless hot water heater's Circ-Logic technology offers recirculation patterns that match your habits; For the latest in non-condensing technology that speeds up service and installation, check out our new RE160iN model

Never Run Out of Hot Water with this Compact Tankless Gas Water Heater: Non-condensing tankless hot water heater from Rinnai is only the size of a small suitcase and fits in a wide variety of spaces, but provides up to 7.5 GPM (5 fixtures at once)

Smart, Durable Design: Includes 12-, 5-, and 1-year residential guarantee and 5-, 5-, and 1-year commercial factory warranty for heat exchanger, labor, and parts, respectively; See Controlr module for WiFi control (not included)

Professional Installation Recommended: Visit the Find a Rinnai PRO page on our website to locate a qualified technician in your area to install your tankless water heater; We do not recommend installing a water heater without a technician

Find Your Rinnai: See our product guides, manuals, energy guide, warranty information, videos, and tables to find the right tankless water heater for your home; Check our Ground Water Temperature Map to see if this heater is optimal for your region

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

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