Why Isn't My Car Heater Working?

January 14, 2021

A close up of a car 's air conditioning control | Lex Brodies

It's a beautiful but cold morning, and you have errands to run. On entering your vehicle and driving off, you suddenly realize the heater is blowing out cold air rather than warm air. You are bound to be frustrated and cold. It could even be downright unbearable. To make it worse, you can't even defrost the mirrors and windows to get rid of condensation. A car heater that isn't working can be the bane of your existence.

So, why isn't the heater working?

Your car heater can stop working due to several reasons:

Ineffective cooling system

Your car's cooling system works like a radiator. Once you ignite your vehicle, the engine heats up to a certain temperature. With the aid of the thermostat, it heats the coolant that is made up of a 50/50 percent ratio of antifreeze and water. The mixture passes through the heating core, and then a fan blows the warm air from the core into the cabin of your vehicle. If the level of the coolant is too low, there's air in the system, or the core isn't working, making the car heater ineffective. If the coolant contains contaminants, it may also prevent the distribution of heated air within the cabin.

A defective fan

Once the fan stops working, heated air will not reach the cabin of your vehicle. Listen in to determine if the fan is running. If you don't hear anything, then the fan is your culprit. A defective fan could be the result of a blown fuse. You may need to replace either the fuse or the fan itself.

Dysfunctional thermostat

If the thermostat gauge is stuck on the 'C,' especially after the engine has had enough time to warm up, then your thermostat is broken. This means it isn't opening up to allow coolant through it to form the core. A dysfunctional thermostat may cause your vehicle to overheat, so consult a technician and have it replaced as soon as you can.

Problems with the heater core

Another possible culprit for your car heater not working is associated with heater core difficulties. The heater core is a cooling system part made of aluminum or brass that carries hot coolant in and out alongside the fans that disperse heat brought in by the coolant. They are responsible for heating and defrosting. Telltale signs that show the heater is not working include fog inside the car, an overheating engine, a fruity sweet-smelling odor, or your car using up coolant very fast.

Water leaks

There are many different places in your car from which leaks can surface. Check your radiator, hoses, and water pump for any damages. If any of these parts are leaking, the car heater will not work correctly.

An effective heating system makes a ride during the cold season much more enjoyable. If you notice any of these heating issues, bring your vehicle to our reputable auto repair shop today for expert attention.

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