When the heat pump compressor has malfunctioned, what mode can the customer switch the system into?

When a heat pump compressor malfunctions, switching the system to emergency heat mode is the appropriate course of action. This mode activates the auxiliary or backup heating system, which could be electric resistance heating or gas heating, depending on the installation. This ensures that the space continues to receive heat even if the main heat pump system is not functioning effectively.

Emergency heat mode is designed to operate independently of the heat pump compressor, allowing the system to maintain a comfortable temperature for the occupants. This is particularly crucial in colder climates where heating is essential for safety and comfort.

In other modes, such as standard or cooling modes, the heat pump relies on the compressor to operate effectively, which would not be possible if the compressor has failed. Idle mode would not provide any heating or cooling, leaving occupants without any heating solution. Thus, emergency heat mode is specifically intended for these situations, ensuring that users are not left without a functioning heating system.