Why is there a thermostat on a heat pump?

Thermostats allow users to turn a heat pump on or off and set the desired temperature. They are also used to set the heat pump to heating or cooling mode.

Heat pumps provide better on-demand performance compared to systems relying on combustion. As a result, the system is able to respond to the room's temperature and start or stop automatically. Thermostats ease this process.

Heat pump thermostats also allow users to set the device to emergency heating mode, which engages an electrical resistance system similar to older electrical heaters. While this mode is useful if the heat pump is unable to meet demand or breaks, it is far less efficient than standard heat pump operation.