Your car is a little room that travels around. Unlike the rooms in your home, the car room has little physical protection from the outside temperatures. You and your passengers are at the mercy of the one car engine to heat and cool the car room while it powers the little rooms travels. The cooling part is easy to understand. The car has an air conditioner. You know what an air conditioner is. Air is pulled in, a coolant makes it cold and a fan blows it through the vents into the passenger area of the car. It works the same way in your home, in the mall, in the movie theater, and everywhere. Heating in the car works quite differently in a car than anywhere else, however.
Heating With Coolant
In your home, a fuel is used to heat air and blow it through vents throughout your house. A car, however, is already producing heat just by running. The trick is to direct heat from the engine into the passenger area of the car without the smell of the engine and with the added ability to control the amount of heat that is added to the passenger compartment. The doohickey that does that is the core heater. The coolant that is also used for cooling picks up heat from the working engine. The warmed coolant flows through the core heater making the hot air which is controlled by the thermostat and directed to the vents by fans.
When things go wrong with your car’s heating system, it can be the fault of the core heater process. As long as the engine is running and there is enough coolant in the engine, nothing will prevent it from becoming warm. The core heater can become plugged or clogged, preventing the coolant from flowing through. Coolant may also not circulate if the pump that pumps it through the core heater is damaged, perhaps by corrosion. Either way, cold air will blow into the passenger area. When that happens, check for corrosion. If the pump is OK, flush out the core heater. That may be enough to return things to normal.
It is possible for the core heater to spring a leak, of course. The best sign of this is the leak itself. Coolant may found on the ground beneath the car or on the carpet inside. Another sign is the odor of anti-freeze. A reliable mechanic can check the core heater and replace it if necessary. Always test the heating system of your car before the weather gets cold each year. If you find your problems early, you can look forward to a comfortably warm traveling room all winter.