Refrigerant Pressure Sensor / Switch: Testing and Inspection

DUAL PRESSURE SWITCH (LOW PRESSURE SWITCH)
1. Turn back the adaptor valve handle all the way and install it to the low pressure side service valve.
2. With the gage manifold low pressure service valves closed, connect the gage manifold high pressure side charging hose to the adaptor valve.
3. Tighten the adaptor valve handle and open the service valve.
4. If there is continuity between the dual pressure switch terminals when the low pressure side pressure is at the level shown in the illustration at left when the dual pressure switch is on, the switch is functioning normally. If not, replace the switch.