High Pressure Sensor / Switch: Description and Operation

A/C PRESSURE CUT-OFF SWITCH DESCRIPTION






The A/C pressure cut-off switch is used to interrupt A/C compressor operation in the event of high system discharge pressures.

- The A/C pressure cut-off switch is mounted on a Schrader valve-type fitting on the high pressure side of the compressor manifold and tube assembly.
- A valve depressor, located inside the threaded end of the A/C pressure cut-off switch, presses on the Schrader valve stem. This allows the A/C pressure cut-off switch to monitor the compressor discharge pressure.
- When the compressor discharge pressure rises to approximately 2896 kPa (420 psi), the switch contacts open, disengaging the A/C compressor.
- When the pressure drops to approximately 1724 kPa (250 psi), the contacts close to allow operation of the A/C compressor.
- It is not necessary to discharge the refrigerant system to remove the A/C pressure cut-off switch.