Refrigerant System Protection

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

A/C PRESSURE CUT-OFF SWITCH
The A/C pressure cut-off switch is located in the discharge line between the A/C compressor and A/C condenser core.

Single Function
The A/C pressure cut-off switch has a set of electrical contacts which are normally closed. When compressor head pressure rises to approximately 2965-3241 kPa (430-470 psi), the contacts open and the compressor operation is shut off. When compressor head pressure drops to approximately 1724 kPa (250 psi), the contacts close again and allow operation of the A/C compressor. Shutting down compressor operation prior to the pressure relief valve set point ensures containment of the refrigerant within the A/C system.