A/C Refrigerant System Operation

R-134a REFRIGERANT SYSTEM
Vehicles are optioned with a R-134a A/C system. The R-134a system uses a Hydrofluorocarbon (HFC) (non-CFC) based refrigerant R-134a. An R-134a system requires the use of Motorcraft YN-12b Refrigerant Oil F2AZ-19577-AC or equivalent meeting Ford specification WSH-M1C231-B. Do not use R-12 tools and equipment on a R-134a system unless specified. Never mix R-12 and R-134a refrigerants and oils. They are not compatible.












A/C SYSTEM - MANUAL
The manual A/C system has a multi-piece, single case design, with an integral A/C blower. The system allows temperature control by delivering heated or cooled air to maintain a constant comfort level. In addition, during A/C operation, relative humidity of air inside the vehicle is reduced. Controls are provided to adjust the temperature and system functions, including A/C blower motor speeds for desired airflow. Outside air is drawn from the cowl air inlet just below the windshield during all system operations except for MAX A/C cooling (when recirculated air is used) and OFF. Manual temperature control can be maintained in all control settings except when the system is turned OFF.

REFRIGERANT SYSTEM
The A/C refrigerant system is a clutch cycling orifice tube type. The system components are:
^ A/C compressor.
^ A/C clutch assembly.
^ A/C condenser core.
^ A/C evaporator core.
^ Suction accumulator/drier.
^ The necessary refrigerant lines.

System operation is controlled by the following:
^ Temperature blend control.
^ A/C evaporator core orifice.
^ A/C cycling switch.
^ A/C pressure cut-off switch.

The refrigerant system incorporates an A/C compressor controlled by an A/C cycling switch. The A/C cycling switch senses pressure in the suction accumulator/drier to control operation of the A/C compressor.

An A/C compressor pressure relief valve is installed in the A/C manifold and tube to protect the compressor against excessively high refrigerant pressures. An A/C evaporator core orifice is used to meter the liquid refrigerant into the A/C evaporator core for A/C evaporator core cooling.