Refrigerant Pressure Sensor / Switch: Description and Operation

2-Function Refrigerant Pressure Switch:

2-FUNCTION REFRIGERANT PRESSURE SWITCh:
To prevent damage to the A/C compressor a 2-function refrigerant pressure switch (S 31/1) is installed in the receiver/drier replacing the previous switch.

1. Function 1 (low pressure) activates if the refrigerant level is too low or with no refrigerant in system.
Cut-out pressure is approx. 2.0 bar.
Cut-in pressure is approx. 2.6 bar.

2. Function 2 (high pressure) activates if the expansion valve becomes clogged or if the auxiliary fan fails to operate.
Cut-out pressure is approx. 30.0 bar.
Cut-in pressure is approx. 22.0 bar.