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  • Stiebel Eltron Tempra 36 Plus

  • Rinnai Sensei RU160iN

  • EcoSmart ECO 36

  • Rinnai RL94eN

  • Rheem RTEX-13

  • Camplux 10L 2.64 GPM Portable Propane Water Heater

Product image of Stiebel Eltron Tempra 36 Plus
Stiebel Eltron Tempra 36 Plus

The Stiebel Eltron Tempra 36 Plus tankless water heater is an all-electric unit designed to support the needs of an entire house. At a flow rate of up to 7.5 gallons per minute, this heater can easily accommodate four or more appliances and fixtures operating simultaneously. The electric heating system runs with virtually no sound, providing on-demand hot water right away.

Like most tankless systems, the Siebel Tempra 36 Plus is estimated to save between 15 and 20% on home energy bills by eliminating heat loss from a standing tank. If your home doesn't have the option for natural gas heaters, then this electric system is a solid replacement.


  • 7.5GPM flow rate

  • Silent operation


  • Users reported electrical failures

  • Lower flow than comparable gas units

Product image of Rinnai Sensei RU160iN
Rinnai Sensei RU160iN

Rinnai is one of the top names in tankless water heating, and their RU160iN unit demonstrates why. These small units save massive amounts of space and energy consumption over a traditional water heater without sacrificing performance. The RU160iN can support anywhere from three to seven appliances or fixtures simultaneously, depending on their individual draw, providing up to nine gallons per minute of hot water.

The built-in recirculation technology offers even faster hot water and can be configured to match your daily usage habits. This tankless water heater, which runs on natural gas and should be installed by a licensed professional, is robust enough to support most people's at-home water needs.


  • Trusted brand name

  • 9GPM flow rate

  • Recirculation technology


  • None we could find

Product image of EcoSmart ECO 36
EcoSmart ECO 36

The ECO 36 tankless water heater is an electric unit with the capacity to support your whole home's water needs. The 36-kilowatt heater can provide between 3.6 and 8.7 gallons per minute. This can support between two and five appliances running simultaneously while saving significant money on your energy bills. The ECO 36 is designed to self-regulate, using only the energy needed to heat the water when you need it. And because it's all-electric, this is a great unit to use in locations that don't have access to natural gas.


  • Easy controls


  • Some users report early failure

Product image of Rinnai RL94eN
Rinnai RL94eN

The Rinnai RL75eN water heater is designed for installation outdoors, freeing up space in your utility room or basement. This unit, powered by natural gas, has a flow rate of up to 7.5 gallons per minute, enough to support up to four different appliances or fixtures simultaneously.

It's robust enough that you can shower, do dishes, wash hands, and run the laundry all at the same time. Rinnai's Wi-Fi controls make adjustments simple and easy, and the recirculation technology brings warm water faster. For those with moderate water use who want the unit installed outside, this is an ideal solution.


  • Can be installed indoors or outdoors

  • Trusted brand name


  • None that we could find

Related content

Product image of Rheem RTEX-13
Rheem RTEX-13

The Rheem 240V RTEX-13 residential tankless water heater is a quality point-of-use hot water heater. With a 3.17GPM flow rate, it's designed to support one to two appliances in a single location, such as a shower in the bathroom.

This is an excellent option for supplying an expansion or addition to your home's existing infrastructure. The digital temperature display and exterior controls make raising or lowering the heat between 80 and 140 degrees Fahrenheit easy. Installation is relatively simple, but should still be left to professionals in most cases, since this is dealing with both water lines and electricity. If you're looking for a small tankless water heater, then this is a quality option.


  • Ideal for point-of-use applications


  • Low flow rate

  • Users report early failure

Product image of Camplux 10L 2.64 GPM Portable Propane Water Heater
Camplux 10L 2.64 GPM Portable Propane Water Heater

The Camplux 2.64 GPM propane water heater is designed specifically for low-use outdoor applications. Perfect for sheds, outdoor showers, or campers and RVs, this tankless water heater can support one or two appliances at a time.

It connects easily and securely to standard propane tanks, with numerous safety features like anti-freezing, automatic gas shut offs, and overheating protection. It's designed with efficiency in mind—the manufacturer claims an 11.5% energy savings from the improved combustion chamber and heat exchangers. For small-use applications or families on a road trip, this is an elegant solution.


  • Easy connection to propane tank

  • Perfect for hot water on the go


  • Low flow rate

Meet the tester

Jean Levasseur

Jean Levasseur


Jean Levasseur became a professional writer over a decade-long career in marketing, public relations, and technical writing. After leaving that career to stay home to care for his twin boys, Jean has continued to write in a variety of freelance roles, as well as teaching academic writing at a local university. When he's not reviewing tools or chasing toddlers around the house, he's also an avid fiction writer and a growing woodworker.

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