Domestic hot water (DHW)

Domestic hot water refers to heated water used for everyday household activities such as bathing, showering, washing dishes, and cleaning. It is typically produced by a dedicated water heater, boiler, or heat pump and stored in a hot water cylinder, or generated on demand through instantaneous water heaters.

The temperature of DHW is usually maintained between 50–60 °C to provide comfort while also minimizing the risk of bacterial growth, such as Legionella. Energy efficiency plays a key role, since water heating can account for a significant share of household energy use.

Modern systems often include features like thermostatic mixing valves, smart controls, or solar thermal integration to enhance safety, comfort, and sustainability. Ensuring a reliable domestic hot water supply is therefore central to everyday convenience and overall building energy performance.

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