Rinnai Corporation develops, manufactures, and sells heating products in Japan, the United States, Australia, China, South Korea, and Indonesia.

The company offers water heaters, including hot-water units, bath hot-water units, hot-water and heating units, gas/solar hybrid hot-water and heating systems, etc.; kitchen appliances, such as tabletop stoves, built-in-stoves, ovens, range food, dishwashers and rice cookers, etc.; and air conditioning appliances comprising fan heaters, fan-forced heaters, infrared heaters, etc.

It also provides commercial-use equipment comprising grills, gas stoves and rice cookers, etc.; and living room and dressing room products, as well as others, such as clothes dryers, infrared burners and parts, etc.

The company offers its products under the Rinnai brand name.

The company was formerly known as Rinnai & Co. and changed its name to Rinnai Corporation in 1971.

Rinnai Corporation was incorporated in 1920 and is headquartered in Nagoya, Japan.