Prizm L4-108 1.8L DOHC VIN 8 MFI (1998)
High Pressure Safety Valve HVAC: Description and Operation
The compressor is equipped with a pressure relief valve (9) which is placed in the system as a safety factor. Under certain conditions, the refrigerant on
the discharge side may exceed the designed operating pressure. To prevent system damage, the valve is designed to open automatically when the high
side pressure exceeds a specified amount. Conditions that might cause this valve to open (defective A/C pressure sensor, inoperative cooling fan, etc.)
should be corrected, and the refrigerant oil and refrigerant should be replaced as necessary.