High Pressure Safety Valve HVAC: Description and Operation

High Pressure Cut-off Switch And Relief Valve:

HR-6 High Pressure Cut-Off Switch And Relief Valve:

PRESSURE RELIEF VALVE DESCRIPTION
The compressor is equipped with a pressure relief valve 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 at approximately 3173 kPa (460 psi). Conditions that might cause this valve to open (defective high pressure cut-off switch, inoperative electric cooling fan, etc.) should be corrected, and the refrigerant oil and refrigerant should be replaced as necessary.