What component is responsible for disengaging the compressor clutch at high pressure?

The correct choice is associated with the high pressure cutout switch, which plays a crucial role in protecting the air conditioning system from excessive pressure conditions. When the pressure within the system exceeds a predetermined level, the high pressure cutout switch is activated. This action disconnects the power supply to the compressor clutch, effectively disengaging the compressor. This protection mechanism is essential to prevent potential damage to the compressor and other components of the air conditioning system that could occur due to overpressure, such as system leaks or even catastrophic failure.

The other components mentioned have different functions. For instance, the expansion valve is responsible for regulating the flow of refrigerant into the evaporator based on the cooling demand. The receiver/dryer primarily serves as a storage reservoir for refrigerant and removes moisture and contaminants from the refrigerant system. The thermal expansion valve also controls refrigerant flow, but it does so based on temperature and pressure changes rather than acting as a safety switch for high pressure. Therefore, the high pressure cutout switch is specifically designed to protect the compressor by cutting off its operation in response to high pressure readings.