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A/C Pressure Cutoff Switch

A/C HIGH PRESSURE CUTOFF SWITCH

OPERATION
The contact between the fan switch terminals is normally open. The contact is closed at 325 psi and the engine cooling fan motor will run at high speed.

The contact will reopen at 275 psi. The engine cooling fan motor will run for approximately 20 seconds after the contact has reopened to ensure that when the A/C compressor turns back on the fan does not rapid cycle between low and high speeds.

The contact between the clutch switch terminals is normally closed. The contact opens at 425 psi, shutting off the A/C compressor. When the pressure falls to 250 psi, the contacts close and allow A/C compressor operation.