Why Is The Heat In My Car Blowing Cool Air?


If your car heater is blowing out cold air instead of heat then it must be fixed immediately. Unreliable car heaters can make the cold winter unbearable. Not just a single component heats your car, there are many components that work together. In this article, we’ll discuss the reasons why your vehicle blows out cool air rather than heat.

Not Enough Coolant

The coolant is made up of 50% antifreeze and 50% water – to cool your engine down, especially this works good in summer.

During the winter the coolant is brought over from the engine to the heater core which blows warm air into your car. 

It produces cool air for a few minutes to warm up the engine. If the cool air continues to blow out, then check the coolant level. When your car is low on coolant, it won’t send any to the heater core to create warm air.

Stuck Thermostat

Thermostats are nothing but the valve that open and close depending on the temperature of the coolant. As soon as the engine is heated, they stay closed until the coolant in the engine reaches a certain temperature. If they fail to open the coolant won’t circulate properly, and the engine may overheat. This can cause a problem where the heater blows cold air.

When the thermostat sticks open, it can prevent the engine from warming up properly or increase the warming-up period.

Air in the Cooling System

Another common problem occurs when air gets into the cooling system. The heater core is often a high point in the cooling system so there are chances for air getting into it and trapped. If this happens, the air bubbles must be flushed out to fix the problem.

Problems with Heater Core

Heater cores are situated directly in the back of dashboards. Sometimes the coolant may not travel through the heater core or the air from the blower motor doesn’t reach the heater core due to clogs. A heater core is a cooling system that resembles compact radiators. The heater core is made of brass or aluminum tubing that carries the hot coolant in and out, the fans are attached to disperse the heat released by the coolant.

Signs of problems with the heater core

Fog inside of your car

A fruity, sweet-smelling odor

If coolant is used very quickly

The engine overheating

Broken or Clogged Heater Controls

If the control buttons are functioning for several years then they may get gummed up and stop working. Though the coolant levels are fine and there’s no problem in the heater core, you have to check the control buttons or your heater control valve. The heater control valve is located below the hood and that works as a switch that turns the heat on and off. If it doesn’t work properly then your car could get stuck blowing cool air into the cabin.

Water Leaks

Leaks can be in different places so be sure to check your hoses, radiator, and water pump for damage. If any of these leaks, your car heater won’t work properly. Contact a professional auto repair shop to fix the issues.

If you ignore these problems, it may cause bigger and more costly repairs. Fix as soon as possible.