car heater issues and how to fix them

7 possible car heater issues and how to fix them

Several things may go wrong with automobile heaters because, like a house heating system, multiple components work together to heat your vehicle. If one or more of these problems exist, your vehicle may produce chilly air rather than heat.

There are multiple reasons why a heater could cease operating, such as:

  • The cooling system has a leak, resulting in low levels of antifreeze/water in the radiator.
  • A faulty thermostat prevents the engine from properly warming up.
  • A broken or malfunctioning blower fan.
  • Coolant that includes rust particles or gets otherwise polluted, preventing the heating core from effectively circulating air into the cabin.

Let’s go into the details of what might be the reason behind your car heater blowing cold air:

Thermostat not working well

If your car’s heater is only blowing cold air, the problem is likely with the thermostat. The thermostat is responsible for regulating the temperature inside your car, and if it’s not working properly, your car will be unable to heat up.

There are a few ways to fix this issue. The first is to make sure that the thermostat is turned on. Sometimes it can be easy to forget to turn it on when you first get in your car. The second thing you can do is check the fuse box. If there’s a blown fuse, it will need to be replaced in order for your car’s heater to start working again.

If you’ve tried both of those things and your heater is still not blowing hot air, it might be time to call a mechanic. There could be something wrong with the wiring or the thermostat itself, and it will require professional attention in order to be fixed.

Low coolant level

If your car’s heater is blowing cold air, the first thing you should do is check the coolant level. Low coolant levels are the most common reason for a car’s heater to blow cold air.

If the coolant level is low, you can add more yourself using a funnel and a bottle of coolant. Be sure to check the levels regularly and add more if needed, to keep your car’s heater running smoothly.

If you’re uncomfortable adding more coolant yourself, or if you think there might be another problem with your car’s heater, it’s best to bring it in for a check-up. A mechanic can help diagnose the issue and will be able to recommend the appropriate course of action.

Heater core problems

One of the most common reasons behind your car blowing cold air is that there’s a problem with the heater core. The heater core is responsible for heating up the air that goes into the car. If it’s clogged or blocked, then the air won’t be able to get hot and you’ll be left with cold air coming out of the vents.

Heater core problems

If you think that the problem might be with your heater core, then you can try and fix it yourself. There are a few things you can do:

  • Pour a pot of boiling water over the core. This will help to clear any blockages and get the heat flowing again.
  • Use a vacuum cleaner to suck out any gunk or dirt that might be blocking the core.
  • Hire a mechanic to take a look at it and fix any problems there might be.

Damaged temperature controls

One of the most common reasons your car’s heat might be blowing cold air is because the temperature controls are damaged. This can often be fixed quickly and easily at home without having to bring your car in for service.

Simply remove the temperature control panel from your car’s dashboard by unscrewing it or pulling it out. If you see any obvious damage, such as a broken switch or a loose connection, you can fix it by gently pushing it back into place or by reattaching the wire.

If everything looks okay but the heat is still not blowing hot air, you might need to replace the temperature control panel. This can be done relatively easily and should only take a few minutes.

Clogged up blend door

One of the most common reasons your car’s heat is blowing cold air is because the blend door is clogged. The blend door is the little door that controls the airflow from the heating and cooling vents in your car.

If your car’s heat is blowing cold air, you can try to fix it by clearing out any debris or obstructions from the blend door. You can do this by using a small object like a paperclip to clear out any gunk that may be blocking it.

Once you’ve cleared out the obstructions, you can try turning on your car’s heat to see if it’s blowing hot air now. If it is, then you’re all set! If not, then you may need to take your car in for a repair.

Pinched heater hoses

Another common issue that can cause your car’s heater to blow cold air is a pinched heater hose. This is a problem that is easily fixed, and all you need to do is loosen the clamps on the hose and twist it back into place. If you are unable to do this yourself, you can take your car to a mechanic, and they will be able to fix it for you in minutes.

Water leak

If your car is leaking water, the likely culprit is the heater core. The good news is that this is a relatively easy fix and doesn’t require too much effort or expertise.

The first step is to shut off the engine and open the hood. Once you’ve done that, you’ll need to locate the heater core. It’s usually in the lower front of the car, near the firewall. Once you’ve found it, you’ll need to disconnect the hoses that are connected to it. After that, you can remove the heater core and take it to a mechanic to have it fixed.

How to fix a car heater

One of the most common car problems is a heater that blows cold air. This can be caused by a variety of issues but is usually easy to fix. Here are a few tips on how to troubleshoot and fix your car’s heater:

Fix a car heater

  • First, check the thermostat. Make sure it’s in the “on” position and that it’s set to the desired temperature. If it is, try turning on the heat and see if the problem persists,
  • If the thermostat is working correctly, there may be something blocking the airflow to the heater. Check for any debris or obstructions in front of or around the heater and clear them out.
  • If there is no debris blocking the heater, it may be time to replace the heating element. This is a more complicated process and should be done by a professional.
  • If you’re still having trouble fixing your car’s heater, please contact a mechanic for further assistance.


If you’re having trouble with your car’s heating system, don’t despair. There are a few things you can do to try to fix the problem yourself. In most cases, it’s a quick and easy process. Try one of the solutions listed in this article, and your car will be nice and toasty in no time.