The heater core in an automobile enables the heat of the engine to be transferred into the cabin. The heater core is the crucial portion of the heating system where the warm air that is blown into the cabin through the dashboard is warmed up. If you have an unusual smell inside the car when you turn on the heat, your heater core may be broken.
As your car burns fuel to generate power and turn the wheels, it also produces heat. If you ever touched the hood of your vehicle after an extended period of operating your engine, you will have noticed that it gets fairly warm. The coolant that circulates through the engine block and prevents the overheating of your engine gets extremely hot and would actually boil if it were not under pressure inside the engine.
This hot liquid is an extremely useful source of heat when trying to warm the vehicle's cabin in winter. By transferring some of this heat into the cabin, it is possible to heat the interior of the vehicle without drawing additional power from the engine. Routing some of the hot fluid to the interior of the vehicle, where it is cooled as some of the heat passes to the air within the cabin, also makes the job of the car's radiator (the primary part responsible for cooling the engine) easier.
A heater core is a relatively simple equipment and consists of a metal pipe that contains hot coolant from the engine. This metal pipe travels through the heater core and a fan blows air that passes through these pipes. Since the pipes are very hot, the air warms up and enters the cabin of the vehicle at high temperatures. The amount of heating can be varied by reducing or shutting down of the water supply into the heater core, which results in the water inside the heater core cooling down quickly.
The heater core is a sensitive part whose failure can have unpleasant consequences. If the heater core begins to leak, you will sense an unusual odor when you turn on the heating system (often a sweet, chemical smell) as some of the engine coolant vapor will enter the cabin. This is very unhealthy for you and will also damage the interior of your vehicle as the chemicals in the coolant may deposit as a thin, greenish film on the interior surfaces of your car.
If a leaking heater core is left unchecked, it can eventually burst and potentially deposit boiling water into your lap. To maximize heating, the heater core, and consequently the water therein, is right behind the dashboard and very close to the occupants. So get your vehicle's heating system checked as soon as possible if you smell anything unusual when you turn on the heater or see a leak from the dashboard.
