Heater System: Description

System is a blend-air type. Outside air is heated and then mixed with cooler outside air to attain desired temperature. System consists of a blower, air inlet assembly, heater air distributor assembly and heater control panel.

Blower, air inlet assembly and heater hoses are located on engine side of firewall, while heater core and distributor duct are on passenger side. System has no heater control valve. Coolant circulation keeps heater core hot at all times.

Operation of blower motor is controlled by fan switch. Motor is connected in series with fan switch and blower resistor assembly.

On Van and Suburban models, an auxiliary heater is available for heating rear of vehicle. Unit operates independently of standard heater and has its own set of controls. Heater hoses connect at standard heater and extend to auxiliary heater. A vacuum-operated heater control valve is installed in inlet line in engine compartment to cut off coolant flow when heat is not desired. See Figure and Figure .