High Pressure Safety Valve HVAC: Description and Operation

COMPRESSOR HIGH PRESSURE RELIEF VALVE

Compressor High Pressure Relief Valve - Typical:

A high pressure relief valve is located on the compressor line manifold, which is at the top of the compressor. This mechanical valve is designed to vent refrigerant from the system to protect against damage to the compressor and other system components, caused by condenser air flow restriction or an overcharge of refrigerant.

The high pressure relief valve vents the system when a discharge pressure of 3450 to 4140 kPa (550 +/- 50 psi) or above is reached. The valve closes with a minimum discharge pressure of 2750 kPa (400 psi) is reached.

The high pressure relief valve vents only enough refrigerant to reduce the system pressure, and then re-seats itself. The majority of the refrigerant is conserved in the system. If the valve vents refrigerant, it does not mean the valve is faulty.

The high pressure relief valve is a factory-calibrated unit. The valve cannot be adjusted or repaired, and must not be removed or otherwise disturbed. The valve is only serviced as a part of the compressor assembly.