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chauffage de la voiture qui ne fonctionne pas

Help! My car heater stopped working!

Well before the end of the year and the arrival of the first frosts, our vehicles’ heating systems merit the same attention we give to verifying the condition of our winter boots, snow clothes or home insulation!

You often don’t have to make an appointment with a mechanic to make sure that your system is working optimally: regular maintenance, proper use and a good periodic cleaning will generally guarantee that it functions perfectly throughout the cold season. However, sometimes the problem may be more serious, requiring the services of an expert. In any event, keep in mind that prevention is always your best strategy. Don’t wait until the last minute to make sure that everything’s under control.

As you’re about to find out, there are numerous causes for car heater problems, and addressing them may very well be beyond your means!

Introduction to car heaters and why they break down

Every heating system has its own unique set of potential problems! Were you even aware that there were different types of car heaters? With a water, air or electric cooling system, certain defects are easier to diagnose than others are. We’ll focus on the system that is most common, namely, water-cooling.

The principle is relatively simple: the warm coolant from the engine passes through the heater core, which is like a little radiator. A fan forces air past the fins and tubes of the core, where the liquid inside warms it before it reaches the interior of the vehicle. While the process may be simple, it’s also long! Now that you have a better understanding of the mechanism, you probably understand why your car has to warm up for a while before the heater can warm the passenger compartment to the desired temperature! Nevertheless, problems rarely occur in the heating system during the first few years of use. It’s more common to find issues in models that are starting to show their age.

The good news?

Regardless of the cause of the problem, it can frequently be resolved.

The bad news?

The problem can have a variety of different causes, including the following:

  1. A jammed thermostat
  2. Air inside the cooling system
  3. A clogged heater core
  4. Expired coolant

If the problem stems from the cooling system, the most common causes are mechanical, electrical or suction related. You should also bear in mind that these causes can vary widely from one vehicle to another. Although blend doors may not immediately come to mind, it’s also wise to check these little air valves. It isn’t unusual for them to stick, even when the heater core is working perfectly. The reason they’re stuck and the way they’re stuck can directly influence the airflow, which, depending on the circumstances, may be partial, total but cold, or permanent but cold…or warm!

Leave the repairs to professionals

The thermostat allows the engine to warm up. It remains closed until the coolant reaches the right temperature at which time it opens to allow the coolant to circulate. If it fails to open at that time, the engine can overheat, resulting in a situation in which the radiator supplies cold air. The solution? Replace the thermostat, which can take a little time…or a lot! In the second case, if air has gotten into the cooling system, the air bubbles can cause a blockage that interferes with the flow of warm air. Third, a clogged heater core can cause the car heater to deliver cold air. The use of compressed air is recommended in order to flush the coolant, debris and trapped air. Finally, for problems linked to your coolant, you should check to see if it’s too old and, if so, drain it and replace it.

What can you do to prevent a breakdown?

There’s no magic involved: removing any obstructions in the system is your best option! Lint, pine needles and other debris are at the root of a good number of problems. Regular cleaning and rinsing will generally suffice to get the situation under control.

However, most of us must admit that our technical knowledge is often too limited for us to know exactly what the problem is and, especially, how to resolve it. Removing obstructions and performing regular maintenance is one thing; however, there’s no guarantee that these actions will prevent your heater from blowing cold air. When that happens, you’ll require the assistance of a professional.

In most cases, a team of professionals can help fix your heating system at an affordable price. On the other hand, the wait times may vary depending on the problem and the professionals’ current workload. That’s why it’s so important to check your vehicle before the start of winter. Consider this annual appointment a long-term investment that will ensure that your vehicle is safe and functional. The advantage? The expense will already be included in your budget, rather than coming as an unpleasant surprise when your car heater breaks down! In the end, you may even save money!

The teams at Trans-Mico have been providing clients with guidance and assistance with their vehicle maintenance for more than forty years. Their goal is to guarantee your peace of mind through courteous service and modern equipment, always taking great care to keep you informed. With them, there are no surprises! If you want to get the straight facts regarding your car’s heating system and general condition, you can definitely count on them!

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