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Control Assembly, HVAC

CONTROLLER OPERATION

BLOWER OPERATION
The operation of the A/C system is controlled by the switch and levers on the control assembly. The compressor clutch and blower are connected electrically to the control assembly by a wiring harness. The blower circuit is open in the "OFF" mode. In all other modes the blower has 4 speeds to control the amount of air flow.

TEMPERATURE CONTROL
Temperature is controlled by the position of the temperature lever on the control assembly. A cable connects this lever to the temperature valve. It controls air flow through the heater core. The position of the temperature valve is independent of mode selection. The temperature cable attaches to the right side of the A/C module.

VACUUM VALVE CONTROL
The remaining functional assemblies are controlled by the vacuum valve linked to the mode lever of the control assembly. This valve controls the supply of engine vacuum to the appropriate vacuum actuator(s) for the mode selected.