The Stiebel Eltron tankless water heater, a powerhouse in the industry ... This Old House emphasizes the advantages of the unit’s indoor installation, which protects it from temperature ...

Rinnai RX199iN Condensing Smart Sense Tankless Water Heater Rinnai RX130iN Condensing Smart Sense Tankless Water Heater ...

Using PTC ceramic heating technology and high-speed fan, the indoor heater can heats up in seconds and delivers a steady stream of warm air to you. Just turn on the electric space heater ...

Wattage and British Thermal Units (Btu) indicate how large of a space a heater can effectively warm up. Watts indicate the energy transfer rate, while Btu indicate the amount of energy used.