Why Does Car Heater Blow Cold Air? 7 Surprising Reasons!

Why does car heater blow cold air? The car heater blows cold air for many reasons, including inadequate coolant, heater core issues, clogged or broken heater controls, dysfunctional thermostat, water leakage, disconnected or lose air intake hose, leaking or clogged heater core.

This car issue, for many reasons, can leave people scratching their heads. If the car heater suddenly blows out cold air and does not heat in the middle of the winter, it’s something to leave you frustrated. An unreliable car heater can make winter months even unbearable. So, let us delve deeper and understand each of the reasons why the car heater blows cold air.

why does car heater blow cold air


Reasons Why Your Car Heater Blows Cold Air

Here are the reasons why your car heater blows cold air.


#1. Inadequate coolant

The vehicle uses coolant consisting of 50 percent water and 50 percent antifreeze that cools the engine down, particularly in the summer months. In the winter, after cranking up the heat, the coolant begins in the engine and the heater core and blows the warm air in the car. That relaxed feeling is felt in the few minutes with the engine warming up. The coolant heats up and emits heat in the interior. With cool air that blows out continuously, you must check the coolant level. A car low in coolant avoids sending heat to the heater core, creating warm air.


#2. Heater core issues

Car heater issues are often associated with the heater core complexities. The coolant does not travel the heater core correctly, and the air in a blower motor does not reach it. Or, heater core minor tubing clogging is occurring. The heater core is a cooling system resembling a compact radiator. It consists of aluminum or brass tubing carrying the hot coolant inside and out, alongside fans dispersing the heat in the coolant.

The heater core is the one responsible for vehicle defrosting, including heating. It is typically situated in the backmost part of the dashboard. Your car that does not blow warm air to the cabin with an acceptable coolant level causes an issue with the heater core. Watch out for possible signs if something is wrong with the car heater core. These signs can include a sweet-smelling and fruity odor, fog in the car, a car that uses coolant very quickly, and engine overheating.


#3. Clogged or broken heater controls

The control buttons can stop working after they gum up. Replacement of the control buttons is necessary with acceptable coolant levels but with no issues with the heater core. This valve is right below the hood and functions as the switch turning the heat on and off. The vehicle can get stuck as it blows cool air to the cabin if the piece does not work correctly.


#4. Dysfunctional thermostat

Even if you heat the engine, the thermostat gauge in the “C” already equates to a damaged or dysfunctional thermostat. This section that does not signal the car with a warm engine would mean the coolant does not send over and provide heat. That is when the air remains calm; the thermostat is an inexpensive and easy fix. Install a new thermostat if you want the device to work again quickly.


#5. Water leakage

This is another reason why your car heater blows cold air, as there are many sections where leaks occur, so check the radiator, water pump, and hose for further damage. Any of these three that arise as they leak is due to a poorly-functioning car heater. It is a practical car heater that makes an enjoyable and warming winter. If these issues occur, call a reliable auto repair shop. One will closely look at the heating system and solve the problems with the car heater right away. Never ignore the problem, or it may bring inexpensive and significant issues along the way.


#6. Disconnected or loosened air intake hose

If connected under the vehicle’s hood, check the air intake hose’s condition. The rubber hose brings fresh air into the engine, beginning outside to run correctly and breathe properly, as this is necessary for the machine to emit heat as it burns fuel in the cylinders. If you drive around but with no hose connected, the car may overheat and may not perform well as needed, as this is something you don’t want to happen. So, tighten up things that seem connected or loose to know if it solves the situation. You may also want to read about how to make car heater warm up faster.



#7. Stuck heater control valve

Why does car heater blow cold air? It is also because a closed heater control valve causes the vehicle to blow some cool air rather than warm air. Do not open this up if you have no experience fixing the inner car’s workings. Or else, it can bring damage, or you get yourself hurt as it gets burned by hot steam. The best solution is to inspect it with professional help. Clean it also as needed to fix it correctly and allow it to heat once again.


It’s A Wrap!

Now you learn the many reasons why does car heater blow cold air. And the moment it occurs, you need to think of these reasons to help you fix it. If you cannot DIY-repair it, call a professional auto shop specialist or let them carry it to their location to repair it more. That way, it will get back to its working condition. Click on these links to read related articles; know how much to fix car heater and car heater not blowing hot air.

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