The internal overload of a hermetic compressor senses which parameter?

• A. Prevents high pressure from going too high
• B. An overcharge of refrigerant
• C. Compressor motor temperature
• D. Low side refrigerant temperature

Answer: (C)

The protection inside a hermetic compressor is focused on the motor by monitoring its winding temperature. The internal overload is a thermal sensor (often a bimetal switch) placed in or near the motor windings, and it opens the circuit when the winding gets too hot. This guards the insulation and windings from damage due to overheating or excessive current. It isn’t meant to sense refrigerant pressures or temperatures; those are handled by other safety devices in the system, like high-pressure or low-pressure switches. Some designs automatic reset once cooling occurs, while others may be a one-shot, but the core idea is clear: protect the motor by watching its temperature.