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High Pressure Sensor / Switch: Description and Operation

HIGH PRESSURE CUTOFF SWITCH

The air conditioning system is equipped with a high pressure cutoff switch. This switch is normally closed, but will open at pressures of 2827-3103 kPa (410-450 psi) in order to interrupt the voltage to the compressor clutch coil. When the high pressure cutoff switch opens, the compressor stops cycling, which prevents the pressure relief valve from discharging the refrigerant and oil.