A/C Cycling Switch

The A/C cycling switch is mounted on a Schrader-type valve fitting on the top of the suction accumulator.

• A valve depressor, located inside the threaded end of the A/C cycling switch, presses in on the Schrader valve stem, allowing the suction pressure inside the suction accumulator to control the operation of the A/C cycling switch.
• The electrical switch contacts open when the suction pressure drops. The contacts close when the suction pressure rises. For specifications regarding operating pressure(s), refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS .
• When the A/C cycling switch contacts close, the A/C compressor clutch field coil is energized.
• When the A/C cycling switch contacts open, the A/C compressor clutch field coil is de-energized and A/C compressor operation stops.
• The A/C cycling switch will control the evaporator core pressure at a point where the plate/fin surface temperature will be maintained slightly above freezing.
• This prevents icing of the evaporator core and blockage of airflow.
• It is not necessary to recover the refrigerant to remove the A/C cycling switch.