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Here are the Possible Reasons Why Your Vehicle Isn’t Blowing Hot Air

Here are the Possible Reasons Why Your Vehicle Isn’t Blowing Hot Air article image by HP Automotive

As summer slowly fades through fall and stretches into winter, most drivers aren’t too worried about their vehicle’s heating system.  It worked excellently last year and even the year before that, so why wouldn’t it work this year? Most often a car’s heating system starts malfunctioning in the last expected times. 

A vehicle’s heating system isn’t as complicated as you might think. It consists of a heater core, a heater fan, a cooling system, and HVAC control that blows hot air into the cabin as the cooled air returns to the system. While it is a simple and straightforward system, a number of issues can arise due to system malfunction. 

With winter a few months away, it is important to learn what could go wrong with your vehicle’s heating system. Let’s take a look at some of them and the measures that you can take to prevent or resolve the issue as soon as possible. 

Contaminated Coolant 

An engine coolant is made up of a precise combination of antifreeze and water which prevents the engine from freezing or overheating. If your car’s coolant contains the right ratio of antifreeze and water, it shouldn’t freeze in the water or get too hot in the summer. Additionally, it ensures that the cooling system can absorb and remove excess heat in the engine. 

When your car’s heating system works during the colder months, excess heat is blown into the cabin to keep you well insulated, as well as defrost the windshield. If your coolant is contaminated, it becomes more susceptible to freezing resulting in engine overheating and malfunction. 

Heater Core Malfunction 

A faulty heater core is a vital part of your vehicle’s HVAC system. It consists of a series of tubes and fins and works similarly to your car’s radiator system. However, while the radiator is programmed to dissipate heat to the surrounding air, the heat generated by the heater core is typically blown into the passenger compartment by a blower fan. 

Due to the structure of a heater core, it is highly susceptible to clogs and leaks. This can reduce the efficiency of the coolant system. Malfunctioning heaters and a contaminated coolant typically go hand in hand. Both of these problems may result in engine overheating and your heating system unable to blow hot air. 

Other signs of a malfunctioning heater core include a sweet-smelling odour in your car, fogged-up windows, and the formation of puddles under the dashboard or passenger floorboard. 

Faulty Thermostat

A car’s thermostat is a valve that opens and closes to control the coolant flow to the engine and radiator. While it is a simple and straightforward system, a properly working thermostat is crucial to ensuring your engine functions optimally. 

A malfunctioning thermostat may become stuck in the open or closed position. When it is stuck in an open position, the thermostat restricts coolant flow which prevents your car from achieving its maximum operating temperature resulting in reduced performance. On the other hand, a thermostat stuck in a closed position leads to restriction of coolant circulation, which in turn can interrupt the system that is responsible for cooling the engine and heating the cabin. 

Malfunctioning Blower Fan

When you run on the heat in your cabin, the heater core then captures the heat from the coolant and then transfers it into the cabin in the form of warm air. The blower fan is primarily responsible for circulating warm air from the heater core and through your vehicle’s vents. When the blower fan is inoperable, you will notice minimal to now airflow coming from the vents. 

There are various issues that may result in blower fan malfunctioning. A blown fuse or damage to a blower fan’s internal components are two of the most common causes of a faulty blower fan. If you don’t feel or hear a breeze while your car heater is running, the primary cause may be your blower fan. 

If you notice any of these issues, it is imperative that you obtain professional help right away. A reputable auto mechanic in Sydney will have skilled mechanics that can determine the primary cause of a malfunctioning heating system. If you live in Sydney, you can always rely on HP Automotive to provide you with professional automotive solutions. Whether you need repairs on your blower fan or replacement of your entire heating system, you can always rely on our team of auto mechanics to get right into resolving your car issues at competitive prices. As a full-service car mechanic shop in Sydney, we offer all types of car maintenance, minor repair, and major repairs to commercial and residential vehicle owners. If you wish to learn more about our services or schedule an appointment, call our direct line on 02 9979 8372 today.