Operation CHARM: Car repair manuals for everyone.

Service Port HVAC: Description and Operation


Service Gauge Port Valves

The high-pressure service gauge port valve is located on the A/C receiver drier manifold and tube assembly.

The low pressure service gauge port valve is located on the manifold of the A/C compressor manifold and tube assembly at the A/C compressor.


Component Location:






The fitting is an integral part of the refrigerant line or component.

Special couplings are necessary for both the high side and low side service gauge ports.

A new Schrader-type valve can be installed if the seal leaks

Always install the A/C charging valve cap on the service gauge port valves after repairing the refrigerant system.