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A/C Pressure Cutoff Switch

An A/C pressure cut-off switch is used on all vehicles 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.







Dual Function
The A/C pressure cut-off switch has two sets of contacts. One electrical contact is 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.