10 Best Electric Tankless Hot Water Heater Reviews - Buying Guide in 2024

【Heating Water in 3s】 When the water passes through the unit, 3000W output tankless electric water heater will heat in 3 seconds, saving your water bill. You can control the temperature according to the water flow.

【Safe Automatic Power-Off】 Automatic power-off when inactive state, over temperature, leaking. And stop heating without water flow, save your electricity bill.

【Easy to Install】 Just install the small water heater on a shelf, wall or bracket under the bathroom or kitchen sink; connect the water pipes up and down to provide hot water for your sink.

【Mini Water Heater】 Install it below the sink, small size saving you space under the sink. Size: 7.87x 5.12 x 2.56". Mini Tankless Water Heater is the best gift for person who has a new sink

【Wide Applications】 Suitable for universal water pipe: 1/2 inch diameter (inflow or outflow),110V;US Plug. Install the small instant hot water heater under American kitchen island, kitchen and living room, enjoy hot water for washing dishes, food, clothes, faces and so on.

【Energy Saving】:Compact and light weight structure with extraordinary energy saving technology. This electric water heater are designed with advanced combustion technology to decrease gas consumption and burning noise. Save more when using our tankless water heater

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, Tempra Plus tankless water heaters can be set to limit the maximum hot water temperature to 109°F. This can be important in some installations to prevent the possibility of scalding.

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

CONVENIENT HOT WATER HEATER: 7 gallon point-of-use mini-tank fits under your sink to provide hot water right where you need it. Thermal efficiency is 98%. Dimensions : 17.5 W x 17.5 H x 14.5 D Inches

INSTALLED VERTICALLY OR HORIZONTALLY: This larger model can be mounted vertically (5.1 gal. of water supply) or horizontally (7 gal. of water supply)- vertical orientation is installed with the cold and hot lines on top of the unit

RELIABLE WATER SOURCE: Easily hard-wire the 7-gallon model to provide the on-demand reliable water source your home or office needs

IMPORTANT INFORMATION: Heating capacity of 1440 watts and a temperature range of 65-145°F max. Operating pressure-150 psi. Water fittings-3/4 inch Male NPT. Electrical requirements (Amp 12A/Volts 120)

EASILY MOUNTED: Can be shelf or floor mounted. Wall mounting available in vertical orientation only (water connections on top) - bracket included. Simply tap into the cold water line and install the water heater directly at the sink to provide 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

ON/OFF Dial Control with adjustable digital temperature display

Self-modulating power control

11kW Model Flow Rate: up to 2.68 GPM

Side 1/2" NPT water connections

On demand, consistent and continuous hot water

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

【INSTANT & SUFFICIENT HOT WATER】 With real powerful 18kW smart heating system, the tankless hot water heater electric ECO180B supplies sufficient instant and endless hot water of 120℉ or higher in seconds, no waiting for preheating nor terrible temp fluctuation during shower time any more and no worry of running out of it. Perfect companion for whole house use, including shower, sink faucets, dishwasher, washing machine, etc.

【SELF MODULATION INSTANT WATER HEATER】The electric on demand tankless hot water heater ECO180B adjusts exact power input based on current flowrate and temp setting. For example, less power will be consumed by the smart water heater when you reduce water flow, thus, you get ideal temperature instead of scalding hot, which ensures comfortable experience and excellent energy efficiency. Also, optimal energy efficiency of 98% saves considerable electric charge for you.

【CONVENIENT USE】The electric tankless water heater 18kW comes with digital display & touch control panel so temp setting is easy job. Best of all, useful information on the screen helps you get full understanding of the working status of the 240v water heater tankless, you needn’t go through hard lesson of temp setting. Now turn on the faucet and let the smart instant hot water heater do the rest.

【SAFE and DURABLE】Newly updated and applied with multiple protections, such as leakage protection, over heating protection and auto stop. Every piece electric tankless water heater ECO180B goes through strict tests to ensure 100% safety and it is listed by ETL and qualifies for UL. Inner water and electricity lines are designed to run separately so as to avoid leakage risk and scale build up. You can expect outstanding performance for years to come.

【POINT of USE WATER HEATER】The sleek tankless water heater ECO180B is compact as shoes box, making it possible to install anywhere point of use to avoid waste, ideal for shower, kitchen, bar, school and hair salon. Please verify it is the right size for you: 18kW at 240V(only); dimensions 12.22" (W) x 17.25" (H) x 4.02" (D); plumbing connections :3/4" NPT. In order to install 18kW Tankless Water Heater it would requires 240V, 2X40AMP Double Pole Breaker and 2X8AWG/2 wires with Grounding.

[Instant Unlimited Hot Water] - REQUIRE 3 SET x Double-pole 40AMP Breakers to Achieve 240V for this On demand tankless electric water heater, providing hot water in 3 seconds when you need it and as long as you need, eliminating wait time, never run out of hot water again and No More cold shower. Flow Rate 5.27GPM @35°F Rise

[Self-modulating Power] - Self-modulating technology regulating the amount of energy required to heat water only when you need it with 99.8% efficient, saving up to 60% on water heating cost comparing to traditional tank water heater. Wall mounted compact size with no water tank, convenient for any spaces, saving floor space and fitting into tight spaces.

[Stable Water Temperature] - Auto adjusting energy consumption basing on income water temperature and flow, ensuring maximum efficiency, continuous stable temperature and optimal power usage. Digital temperature display allowing adjustment in 1° increment from 80°F to 140°F. Heating element separated from water tube significantly reducing scale, corrosion and mineral buildup on the element, achieving better performance and low maintenance.

[Easy Installation & Safety Protection] - ETL certified with overheating protection, auto stop heating when detecting no water, quality workmanship for leakage protection

NOTE - Make sure this water heater is the correct size for your hot water need: 27kW at 240V draw max 114Amp; Required breaker 3 x Double-POLE 40AMP; Wire gauge 3 x 8AWG; Unit size 17.12" x 13.12" x 3.12"; Water connection 3/4" NPT. 2-year limite warranty and 24/7 customer support services.

☼ 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.

ON/OFF Dial Control with adjustable digital temperature display

Self-modulating power control

8kW Model Flow Rate: up to 1.95 GPM

Side 1/2" NPT water connections

On demand; continous hot water