The "S" and "D" on an AC compressor stand for "Suction" and "Discharge", respectively. These letters indicate the ports on the compressor where the refrigerant enters and exits.
- Suction (S): This is the port where low-pressure, low-temperature refrigerant vapor enters the compressor.
- Discharge (D): This is the port where high-pressure, high-temperature refrigerant vapor exits the compressor.
The compressor compresses the refrigerant vapor, increasing its pressure and temperature. This hot, high-pressure refrigerant then flows to the condenser, where it releases heat and condenses into a liquid.
