Why is my AC Broken?

Driving while your AC is broken, when heavily relying on your car can quickly become a nightmare. Having to take the kids to school, run errands, and drive to work with windows rolled down can make things uncomfortable fast.

No matter the time of the year, if your car aircon system decides to stop working, it can make travelling in the car unbearable.

Are you worried the auto mechanic or auto electrician are just making up problems while trying to take advantage of you, and quoting you the highest possible price for parts that may not even need replacing?

Perhaps you are too busy to do adequate research into the problem?

We will discuss the most likely reasons your AC is no longer working, so that you can get cool, and have it fixed ASAP.

There are many different causes of a broken AC, which include the following:

  • Electrical Issues
  • Failed compressor
  • Low or no refrigerant
  • Foul or clogged system
  • Ventilation system

If it sounds like I’m speaking a foreign language, no need to worry.

Unless you are passionate about cars, or an auto mechanic, it’s highly unlikely you would know what these issues are, and why they may be the cause of your broken car aircon system.

Let’s break them down, and take a look at each more closely.

Failed Compressor

One of the most common causes of a broken AC is that the compressor has failed. Wait, what exactly is a compressor? Think of a compressor as the heart of your car’s air conditioning system, as it pumps it produces cool air. If it can’t beat anymore, then the system work properly.

Why did the compressor fail?

Wear and Tear – A compressor can fail from general wear and tear caused over many years and thousands of kilometres.

Oil – Another cause may be that there is not enough oil in the system.

Debris – It’s also possible there is debris in the air conditioning system.

Car undergoing repairs in a workshop, with the hood open for access to the engine.

How to check for a failed compressor?

So how exactly does one check if the compressor is the reason your AC is broken? You need to measure the pressure rise across the compressor. If the pressure is lower than normal, it’s a sign that the compressor has already failed, or is on it’s way out.

If it’s a failed compressor, you simply need to get the compressor replaced, and you will have your car AC system working again in next to no time!

How to fix it?

If it is discovered the refrigerant level is low; the best solution is to add more refrigerant to the car aircon system to bring it back to life, and working again as it should. They will also make sure to seal the leak to ensure that the refrigerant does not leak again in future.

Ventilation System

A problem with the ventilation system can be one of the most misleading and confusing causes of a broken AC.

But why? The ventilation system has a blower, which moves air through a series of ducts and directs it through different passages depending on the vent chosen and the temperature setting.

What Causes a Ventilation problem?

If the ducts end up clogged, or the ventilation doors break they can no longer direct the ventilation air, which can cause the cool air to become warm.

This makes it seem as though you have a problem with a malfunctioning car aircon system even though the AC is still working perfectly.

How to check the Ventilation System

To check if it’s a ventilation problem instead of an AC issue, you can check the feed line to your evaporator. Does it feel cold under the car hood, even though there is warm air blowing into the car from the vents?

If this is the case, then it is a ventilation problem, and replacing the damaged ventilation components will fix the problem.

Foul or clogged system

Another possible problem leading to a broken AC is caused by fouling or clogging your system. Uh, say what?

Using low-quality leak stop agents may be the cause. Or if your AC system has recently been opened, debris may have gotten into the system doing damage.

If the system is clogged, this will lead to pressures changing in incorrect sections of the system and will lead to reducing the cooling effect of the AC.

How to check for clogs

To check for clogs, a mechanic will inspect the pressures around the system, and look for any abnormalities. If they discover a component is clogged, then it’s advisable to replace that component.

Leaking Refrigerant

Perhaps the most common cause of a failed car aircon system is that there is a leak, which can cause your refrigerant level to drop, or even worse completely empty.

What Causes Leaks?

Due to the nature of refrigerant used in a car air conditioning system, it is highly common that leaks occur, which is amplified by the operating environment the system is exposed to.

How to check for leaks?

To check for a refrigerant leak, they will measure the low side pressure which is in the AC system. If the pressure is lower than normal, it’s highly likely that there is a leak which is the cause of a low refrigerant level.

Car undergoing inspection in a workshop setting.

Electrical Issues

There are countless electrical issues which may be the cause of your air conditioner breaking or malfunctioning, such as:

– If the ventilation system does not give the compressor the signal to turn on, then the air conditioning won’t cool the vehicle.

– The electric fan cooling your condenser has blown a fuse, burnt out, or has a bad relay, which will result in the car aircon system malfunctioning at low speeds.

– One of the sensors in the AC fails which can lead the system to give incorrect readings, and not work properly.

Following these tips and regularly having you AC checked for possible problems can help you prevent future issues with your air con, leading to a reliable car you can count on and trust. Enjoy the moment with your family and loved ones, instead of worrying if your car is going to last the journey on a summer day.

If you need further advice, or for a certified technician to assess your vehicle’s  air condition, call us on (07) 3269 3158 or reach out to us. We are located 113 Connaught Street Sandgate QLD 4017. Feel free to visit us at any time.