Vacuum Solenoid Valve HVAC: Testing and Inspection

Fig. 22 Vacuum Switching Valve Port Identification.:

1. Disconnect two-pole connector from vacuum switching valve and remove vacuum hoses.
2. Check valve by blowing air into pipe A, Fig. 22. Air should not be felt coming out of pipe B.

Fig. 21 Vacuum Switching Valve Test.:

3. Connect ammeter and 12 volt battery in series with valve lead wires, Fig. 21. Check valve by blowing air into pipe A. Air should be felt coming out of pipe B. Current flow should be .25 amp. maximum. Replace valve if defective.