A/C System - Manual

REFRIGERANT SYSTEMS
This vehicle has the R-134a refrigerant system.
^ The R-134a system uses a non-chlorofluorocarbon (non-CFC)-based refrigerant.
^ R-134a is a Hydrofluorocarbon (HFC)-based refrigerant.

The A/C refrigerant system is an A/C clutch cycling orifice tube type. The system components are:
^ A/C compressor
^ A/C clutch
^ A/C condenser core
^ A/C evaporator core
^ suction accumulator/drier
^ necessary connecting refrigerant lines

System operation is controlled by the following:
^ A/C evaporator core orifice
^ A/C cycling switch
^ A/C compressor pressure relief valve
^ A/C pressure cut-off switch

The refrigerant system incorporates a 10-cylinder A/C compressor controlled by an A/C cycling switch connected in series with the A/C clutch.

The A/C cycling switch:
^ senses A/C evaporator core pressure to control A/C compressor operation.
^ uses this method of A/C compressor control to stop A/C compressor operation during ambient temperatures below approximately 10°C (50°F) and to prevent A/C evaporator core icing during normal system operation.

An A/C compressor pressure relief valve is installed in the high-pressure side of the A/C manifold and tube to protect the refrigerant system against excessive refrigerant pressures.

Operation of the A/C clutch is dependent on signals from the Powertrain Control Module (PCM). The system is programmed to interrupt A/C compressor operation when certain conditions exist. The A/C clutch can be shut off for several seconds under the following circumstances:
^ at engine start-up
^ at high engine speeds
^ during heavy acceleration
^ when the engine coolant temperature exceeds a predetermined temperature

An A/C evaporator core orifice is used to meter the flow of liquid refrigerant into the A/C evaporator core for passenger compartment cooling.