What Causes Your Heating and A/C Systems to Stop Working?
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Keeping your vehicle’s cabin at a comfortable temperature is important. Hot cars can kill and a cold car can leave you shivering behind the wheel. However, despite sharing a similar function, the heating and air conditioning systems in your car or truck are actually separate. Both require regular maintenance to work properly as your vehicle ages.
It’s fairly abnormal for your air conditioning and heating system to fail simultaneously, as different components affect each system. Here are three common reasons your heating might not be working and three reasons your air conditioning might not be.
Heating System – Low Coolant and/or Air in the Coolant
Your vehicle draws heat from the coolant engine to warm up its cabin. The coolant is drawn to the heater core from the engine block, preventing it from overheating. The heater core sends heat from the coolant to the air that blows into your cabin.
Low coolant means there’s less heat available at the heater core, so the air blowing into your cabin may not be warming up.
When you have air in the coolant system, the hot air can become trapped, as liquid removes more air than plain old air does. When too much air is trapped in the coolant system, it cannot evacuate enough heat to warm the cabin. Again, this can lead to the engine overheating.
Heating System – Malfunctioning Thermostat
The thermostat regulates the temperature of your vehicle, similar to how it does in a home. If the thermostat has failed or malfunctioned, your car’s heater may only work intermittently or not at all. The best way to fix this is to replace the thermostat.
Heating System – Bad Heater Core
Your automobile’s heating core is a small radiator that’s made of aluminum or sometimes brass tubing. It allows the coolant drawn from the engine to circulate, and the excess heat is blown into the cabin.
However, the heater core is prone to many problems, including clogging, air from the fans not reaching it, and coolant not moving as it should. This part of your heating system should be maintained and checked on when you bring your vehicle in for maintenance.
Cooling System – Low Refrigerant
Low coolant can cause problems with the heating system, and low refrigerant causes problems with the cooling system. In fact, if your car or truck’s cabin isn’t cooling as it should, this is the first thing you or your mechanic will check.
Often, the air conditioner will make noises if the refrigerant is low. In addition, it may also blow only cool or warm air, not cold air. Topping up the refrigerant will fix this problem.
Cooling System – Damaged Condenser
One of the reasons you may want a mechanic to look at problems with the cooling system before you decide to add more refrigerant is so that leaks and clogs in the condenser can be ruled out. A leak means the refrigerant you added will just leak out, wasting time and money, and build-up at the front of the condenser will restrict the refrigerant’s flow.
Cooling System – Damaged Compressor
The air conditioning condenser is where the heat exchange occurs. This allows the A/C system to deposit heat outside. Unfortunately, to dump out the heat, the condenser is installed in the front of the vehicle, where debris from the road can fly up and damage it. A rupture can leave the condenser leaking refrigerant and will need to be replaced to prevent further damage.
Is There Any Way to Prevent Problems?
A good way to prevent problems with your A/C and heating systems, aside from bringing your vehicle to a mechanic for maintenance, is to run them periodically. Even in the dead of winter, open up the A/C for a few minutes, and in the blistering heat of summer, let the heat run for a few minutes. This keeps the components going when they aren’t being used very often.
Naturally, don’t freeze yourself by sitting in a cold-blowing car in the winter, and don’t subject yourself to damaging heat by sitting in a sweltering car in the summer. Use common sense, and your air conditioning and heating systems should stay in good shape.