Car Overheats When the AC is On – What Should You Do?

The overheating of your car’s engine should not be overlooked, but what should you do if you notice that upon switching on your AC on a hot day, the engine starts to overheat? That’s exactly what we will focus on here.

If your car overheats when the AC is on you should switch off the AC and stop the car until it has cooled down. Once the car has cooled, you should drive the car home and check for problems or arrange to take it to a mechanic. To fix it, the radiator, AC fan, or compressor may need replacing.

It’s sometimes difficult for drivers to keep track of what’s going on with their car. It’s quite obvious though when warning lights on your dashboard start telling you there is an overheating problem that comes on when there’s a problem with the cooling system. This problem often occurs when a driver leaves their AC on while driving in hot weather or traffic-related stop-and-go situations.

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What are the Signs of an Overheating Car?

It is important to know the signs of an overheating car. This way, you can prevent it from turning into a potentially dangerous problem.

There are different signs that you may notice if your car is overheating. One sign is that your engine will sound unusually loud and shake along with the engine. If this happens, then it is best to stop driving the car immediately because it could cause major damage or even break down completely.

If the engine is noisy and sounds like it wants to stall, then there may be a problem with the car’s cooling system. Another sign of a car overheating is when your car’s temperature gauge goes up too high. The best time to keep an eye out for this type of warning sign is during periods of high heat or prolonged driving in hot weather.

Yet another sign that might occur is steam coming out of the exhaust pipe, which could mean there are serious problems inside. The last major sign of an overheating car would be oil coming out of the exhaust pipe or smoke coming from under the hood or rear bumper area. Let’s hope you don’t experience any of these symptoms!

Here are a few more warning signs that one might see when their car is overheating:

-Rapid rise of the engine’s temperature

-Loss of power steering or braking assistance.

-Steering wheel becomes difficult to turn.

-White smoke coming from the tailpipe.

-Loud hissing noise from the radiator area.

How Does AC Impact Your Car’s Cooling System?

The air conditioning system in your car is an important part of the vehicle’s cooling system as it helps regulate the temperature and humidity inside your vehicle while you’re driving to keep you and your passengers comfortable.

The air conditioning system in cars uses a lot of energy and requires a lot of water, which can lead to problems such as leaks, inefficient operation, and increased wear and tear on the vehicle. However, there are some ways to help make your car’s air conditioning system last longer.

A car’s AC system is a closed circuit that takes the heat from inside the cabin and cools it down by blowing air over a cooled condenser. The air from the AC system gets heated up again, but this time it is blown through a radiator to cool it down before returning to the cabin.

The AC should be checked periodically for leaks from hoses, seals, or fittings because these things can cause trouble down the road. When it comes to cleaning or troubleshooting a clogged condenser or evaporator coil, it is recommended that you contact a professional before proceeding with any repairs yourself.

There are two main reasons why your car can overheat. One is because the AC is on and the other is because the radiator cap is loose.

Mike Mahoney, who has over 45 years of experience repairing cars he has owned, discusses on Quora why turning on the AC can cause your car to overheat. Basically, the AC loads the engine because it requires energy to drive the compressor and AC blower. There is also extra electricity required to power the AC which also adds to the demand placed on the electrical circuits of the car.

The additional load of the AC on the engine produces heat and the coolant system needs to work harder to reduce this heating effect. Also, heat generated by the AC condenser coil passes through the radiator and warms up the airflow to a higher level.

If everything in the cooling system works efficiently and has been serviced so that it is in good condition, then the extra work the cooling system needs to do will not be barely noticeable. However, if there are any problems with the cooling system, overheating can occur when the AC is on.

Car Overheats When the AC is On
Source: Wrench

So what faults in the cooling system need checking if your car is overheating when the AC is on?

Here are a few problems that can cause overheating when the AC is on:

  • A clogged or rusty radiator.
  • Anti-freeze has not been changed for a long time.
  • The electrical fan which should switch on when the AC operates has stopped working.
  • The water pump is not working correctly.

There are other possible faults such as a thermostat that doesn’t work properly or damaged hoses in the coolant system, but these will cause overheating in situations where the AC is not on, this is why I have not included them above.

What Should You Do If Your Car Overheats When The AC Is ON?

Air conditioning will cause an increase in engine load, which will lead to higher engine temperatures, something that can lead to engine problems if not addressed properly. The simple solution would be to turn off or reduce the use of your AC while driving on long trips. Keeping your windows open and increasing your speed would also help keep your car’s temperature at bay and should be considered as well.

Overheating can damage your engine if it happens over time and it may cause other faults in components near the engine. Therefore, this problem needs to be fixed as soon as possible. If your engine overheats for any reason, stop and let it cool down before checking the obvious, such as not enough water in the cooling system.

If the overheating happens only when you turn on the AC then temporarily you need to turn it off and keep it off until you can look at the car or have it looked at by a professional. Remember that the overheating may cause a breakdown or serious damage to your car which will cost a lot to fix!

How to Fix & Prevent an AC-related Overheating Problem in Cars

Many people are not aware that an AC-related overheating problem in cars can be very dangerous to components near the engine. The modern car has a lot of electronics, which means they are more prone to overheating.

The most common cause of this problem is the improper installation of the cooling system parts. A short circuit or faulty installation of any wiring could also cause it.

A cooling system needs to have a very good level of ventilation, especially when working on hot surfaces like engine blocks. Even if your car is running well now, it’s necessary to keep an eye on these issues for optimal performance and safety in all conditions.

When your car overheats when the AC is on, it could mean that either the fan belt isn’t functioning properly or there’s some kind of blockage in your cooling system. If you’re unable to fix this issue on your own, you should call a mechanic for assistance.

To prevent an AC-related overheating problem, it is essential to keep the charge of the battery up, and also to check all hoses for leaks.

One of the most important ways to keep your car running cool in hot weather is to keep your engine well-maintained. This includes checking pipes for damage and leaks, as well as replenishing fluids like antifreeze. Other tips include checking your air filter regularly and topping up your coolant levels if needed.

Another important thing that you can do if overheating is a problem is to flush your cooling system and make sure that no air is in the system as this can cause pockets of heat in the system and slow down the removal of excess heat from the engine. (see this page for more reasons your car may be overheating).

It is common practice to replace the coolant in the system completely at least every two years. Getting your car regularly serviced by a professional will ensure that this job is not neglected and that the condition of your hoses and other important components in the cooling system is maintained and checked and if faulty parts are found, they should be replaced.

In other words, regular servicing and maintenance of your car at set intervals goes a long way to prevent a problem like overheating when the AC is turned on.

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