Grand Cherokee 2WD L6-4.0L VIN S (1997)
High Pressure Safety Valve HVAC: Description and Operation
Fig.5 High Pressure Relief Valve
The high pressure relief valve is located on the compressor manifold. This component prevents damage to the air conditioning system if excessive
pressure develops.
The high pressure relief valve vents a small amount of refrigerant necessary to reduce system pressure and then reseats itself. Excessive pressure may be
caused by condenser air flow blockage, refrigerant overcharge, or air and moisture in the system. The majority of the refrigerant is conserved in the
system.
The valve is calibrated to vent at a pressure of 3445-4135 kPa (500-600 psi). If a valve has vented a small amount of refrigerant, it does not necessarily
mean the valve is defective. The valve closes with a minimum pressure of 2756 kPa (400 psi).
