Low Pressure Sensor / Switch: Description and Operation

Low Pressure Switch

Purpose and Operation
A low pressure switch is used on the suction line from the accumulator. This switch will open if the low side pressure falls below approximately 15 PSI (1 bar). This will interrupt the power supply to the A/C compressor to prevent it from being damaged.


The switch no longer must be removed to gain access to a low pressure service port. A service port is now located on the A/C compressor suction fitting. The terminals on the low pressure switch should, however, be bridged when servicing the system.