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A/C - Tips On Heater Output

NO.: 92-I-10

DATE: August, 1992

SUBJECT:
Information on Heater Output and Defrosting of the Windows

TO: Saturn Fixed Operation Managers

During extremely cold weather, -29~C (-20~F) or colder, the fan control switch should be set to a slow-speed position (fan speed I or II) to maintain the hottest air flow. When the heater fan is set on a high-speed, the engine's coolant temperature may decrease quickly during idle and cool air will flow from the outlets.

If the engine's thermostat is suspected, it should be checked using the service procedures in the "Engine - Mechanical Service Manual." If the thermostat is found to be within specifications, replacing it with another thermostat will not increase the amount of heat available from the vehicle's heater.

Fogged or icy windows can be eliminated by setting the air control lever to defrost. This directs the air flow through the windshield defroster outlets and onto the windshield and front side windows. The temperature setting should be on Full Hot. The recirculation button should be left off. To quickly clear the windows of fog, push the A/C button On, and put the fan control on HI. This will dehumidify the air in the car.

This information is currently found in the first edition of the "1993 Owner's Handbook" in the "Engine Coolant Temperature Gauge" section and will also be located in the "Comfort Controls" section in the second edition of the "1993 Owner's Handbook."