F 350 4WD Pickup V8-351 5.8L VIN H EFI (1997)
High Pressure Safety Valve HVAC: Description and Operation
Under extreme pressure conditions, the A/C compressor pressure relief valve will momentarily open, allowing refrigerant vapor to escape. This relieves
excessive pressure (3172 kPa or 460 psi and above) 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.
