PRESSURE TAPS: Filter driers can be purchased with Schrader valves (pressure taps) on their inlets and outlets (left), or just on the inlet (right). A pressure drop of more than 2 psi measured with ...

• Receiver outlet valve (king valve) partially closed off. Many technicians believe that when any part of the system’s high side is restricted or plugged, head pressures will elevate. This is simply ...