HEATER CORE & HEATER CONTROL VALVE

by Jim Miller

Basically, a heater core is a water to air heat exchanger which is found under the right side of your vehicle’s dashboard, typically covered by a heater box. The main function of the heater core, being of course a part of a vehicle’s heating system, is to provide heat to the passenger compartment. This function, however, is a result of its coolant cooling function (yes, I know, this sounds odd). Coolant enters the heater core via a hose on the vehicle’s cylinder head. With the help of a fan, heat absorbed by coolant is transferred to the air flowing through the heater core. Partially cooled, the coolant then flows back to the pump. So, essentially, heat is provided to the passenger compartment of a vehicle by using the heat from the hot coolant, blowing a fan over it (the heater core) which creates hot air which is then blown into the vehicle’s interior.

Put another way, the heater core resembles a small radiator and is located in the HVAC module. The heater core is connected to the engine cooling system and is used as a heat source for the HVAC system. Engine coolant flows into the heater core and the heat contained in the coolant is transferred to the fins of the core. Air is blown through the core fins by the blower motor fan, where it absorbs heat for delivery to the passenger compartment.

The heater core is an important automobile component which shouldn’t be ignored. It is responsible not only for heating the passenger compartment during the winter, but also for aiding the radiator in cooling the engine all year long. Failure to take proper care of the heater core will cause, among other things, coolant leaks. If this should happen, the efficiency of a vehicle’s cooling system would surely be affected, causing an expensive auto repair job.

Heater core repairs are usually costly and replacement units are not that affordable either. But if, for any reason, the heater core of your vehicle gets severely damaged, be always assured that you can find a high quality and high performance replacement heater core at your nearest auto repair parts shop.

The heater control valve is used as a shut off valve to control coolant flow through the heater core. There are many types and designs of heater control valves. The heater control valve can be operated by vacuum or cable controls. Vacuum can be used to open the valve or it can be used to close the valve. Cable controlled valves normally operate in conjunction with the cable that controls the vehicles interior temperature level.

(Jim is a lifelong fan of Dodger Baseball and used to race sprint cars in the 1980s.)