Refrigerant System Protection

A/C Compressor Pressure Relief Valve






Under extreme pressure conditions, the A/C compressor pressure relief valve located in the discharge manifold at the top of the A/C compressor, will momentarily open, allowing refrigerant vapor to escape. This relieves excessive pressure that might damage the A/C compressor. The A/C compressor pressure relief valve closes as soon as pressure is lower than the relief setting. This prevents loss of the complete refrigerant charge.

A/C Pressure Cutoff Switch
The A/C pressure cutoff switch is located in the discharge line between the A/C compressor and the A/C condenser core. The A/C pressure cutoff switch has two sets of contacts. One electrical contact is normally closed.
^ When compressor head pressure rises to approximately 3242 kPa (450 psi), the contacts open and the A/C compressor operation is shutoff.
^ When head pressure drops to approximately 1724 kPa (250 psi), the contacts again close and allow operation of the A/C compressor.
^ Shutting down A/C compressor operation prior to the A/C compressor pressure relief valve set point 3103 kPa (450 psi) ensures containment of the refrigerant in the A/C system.