When those frosty mornings roll around, you will be glad to have a heater in your car so you can make your trip to the office more pleasurable. Yet sometimes, this system may fail to give you the required comfort but may produce some odd special effects instead. What should you do if something goes wrong with your heater core?

How the System Works

The heater core (also known as a heat exchanger) is a central component in the system and is, in effect, a miniature radiator. It's directly connected to the engine coolant system, and some of the heated liquid that comes out of the engine block is diverted to the exchanger to provide your artificial heat.

Where Is the Heat Exchanger?

The heat exchanger is found between the bulkhead and the dashboard and is quite difficult to access without a lot of dismantling. As with the primary radiator, this heater core can develop problems over time, including corrosion and sedimentation buildup.

You'll certainly want to avoid any malfunction if you can. Should any liquid leak out of the heater core, it could come into contact with some of the sensitive electronics hidden within the dashboard. The carpet may also get damp, which could lead to mould and mildew.

Strange Symptoms

When the heat exchanger does begin to fail, you will notice some odd symptoms.

• The inside of the windscreen may get covered with a greasy film. Some coolant will start to evaporate as it leaks out of the core and gets into the ventilation system. Unlike the traditional fogging that you may expect in certain temperature conditions, this may actually leave some streaky smears on the windscreen when you try to clear it.
• You may also notice an odd, sweet smell. This is the coolant that is now starting to leak into your passenger cabin, and the smell could become even stronger as the engine begins to heat up.
• When you open the bonnet, you may notice that the coolant level is lower than it should be, and you may need to top it up regularly. Once again, this is a sign that the heat exchanger may be starting to leak.

What You Should Do

To avoid all these problems, ensure that you take your vehicle in for service whenever requested. A mechanic will be able to look at the heat exchanger and make any repairs as needed. If the unit is already malfunctioning, this is definitely a job for a professional mechanic, as the core is very difficult to access.