A/C Pressure Cutoff Switch

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

The A/C pressure cut-off switch is located in the A/C manifold and tube between the A/C compressor and the A/C condenser core.

The A/C pressure cut-off switch has a set of contacts. The electrical contacts are normally closed.
- When compressor head pressure rises to approximately 2896 kPa (420 psi), the contacts open and the compressor operation is shut off.
- When head pressure drops to approximately 1724 kPa (250 psi), the contacts again close and allow operation of the A/C compressor.
- Shutting down compressor operation prior to the pressure relief valve set point of 3103 kPa (450 psi) makes sure the refrigerant is contained in the A/C system.