Why Your Car Heater Is Blowing Cold Air (6 REAL Reasons)

Dominic Mitton
By Dominic  • Reviewed by Ben  • Updated:   October 26, 2023
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Sitting in a cold car in the winter and freezing isn’t the coziest feeling, but no worries, you’re not the only one.

Car heaters blowing cold air is a pretty common car problem, but still, it’s one of the most frustrating issues you can deal with.

There are a few basic issues that are leading to your car heater not working properly, so let’s dive deep into each one.

6 Reasons Why Your Car Heater Is Blowing Cold Air

1. Coolant in the engine is low

Your car’s AC system is run by coolant as it cools the engine down, that’s why it’s normal that the heater blows out cool air for the first minute or two.

Coolant is transferred from the engine to the heater to push the warm air and heat you as soon as possible.

When your coolant is too low, it won’t be transferred to the heater core and distribute warm air – so check your coolant levels.

It’s the same principle as with space heaters.

2. Problem with the heater core

When the heater stops working, it’s expected that there’s an issue with the heater core.

It could be possible clogging or blocking within the heater core or simply coolant isn’t able to transfer correctly to the blower’s motor.

It’s important to figure out the exact issue within the heater core to prevent further, more serious damage.

Some of the most common signs of heater core problems are:

  • Fog inside the car
  • Weird smelling odor
  • Car draining coolant quickly
  • The engine overheats easily

3. The thermostat stopped working

The best sign that your thermostat isn’t working properly is if you notice that your temperature gauge still shows “C” after you start your car.

When the thermostat isn’t working properly, it won’t be able to “communicate” with other parts of your car (such as the heating system) and it won’t blow the desired air temperature.

4. Heating controls stopped working

Sometimes your heating controls might be broken or stop functioning – this is usually the case with older cars.

When these controls are broken, it’s impossible for your heating system to listen to selected commands.

5. There are water leaks

As with everything else, your car might have some water leaks.

This is a common issue with bathroom heaters due to humidity.

Cars work with multiple parts working together, so water leakage could ruin your heating system.

In most cases, there’s a water leak in one of the car’s hoses, water pump, or radiators.

6. The cooling system has air in it

It can happen often that air gets stored in the cooling system which affects your heating system as well.

This is most common after the summer is finished and you just have to flush out all the air bubbles and everything will work properly.

These 6 reasons are the most common ones and they usually will get your heating system to work properly – without having to visit mechanics.

If you still haven’t solved this problem after resolving these 6 issues I’ve just mentioned, then it might be time to reach out for professional help to prevent further damage.

Car heating is important same as your household heating, so you can look at multiple ways to heat your home efficiently.

Hey there! I am Benas, the founder and content editor at Home Caprice. Thanks for reading the article. I hope you were able to find what you were looking for. I and my team are here to simplify heating and cooling for everyone. Please have a look at the About page for more details about our website and feel free to check out our editorial process.