9 Causes of Car AC Compressor Failure

Air conditioning is now standard on most trims of most vehicles. You may think that because your car is smaller than your home, the AC system in the vehicle is smaller and, therefore, requires less attention. This is a common misconception.

One reason is that your vehicle’s AC system needs to come on and cool its space from over 37.7°C to under 24°C in a handful of minutes. Depending on your schedule, you sometimes have to perform this task a few times daily. No home’s AC system is expected to be able to do that. Your car’s AC system has all the expensive bits, even that sneaky refrigerant gas always trying to escape.

One common vehicle repair that stings vehicle owners is a failed AC compressor. This is a repair that might be costly $1,000 to resolve. The AC compressor reduces the volume (compresses) of the refrigerant gas used to complete the refrigerant cycle in the system. One way to think about the compressor is that it does all the hard work. To do that, it needs energy, which it gets from your engine via a pulley and shaft.

The excellent news about AC compressors is that most of them are in plain view inside the car in the engine bay. The serpentine belt or accessory belt powers the compressor, so it needs to be where the belt can turn the pulley.

What causes a car AC to stop working?

Car ACs are machines that run hot, making pressure for half the year, and then they sit idle, not moving for half the year. That is not a recipe for a happy machine.

1. Blocked condenser: Responsible for removing heat from the refrigerant, allowing it to cool down before it enters the evaporator. If the condenser becomes blocked by dirt, debris, or other obstructions, it can’t efficiently dissipate heat, leading to poor cooling performance or complete AC failure.
2. Electrical issues: Problems with the electrical system can cause various components of the AC system to malfunction. This can include a faulty AC relay, damaged wiring, or a malfunctioning control panel. Without proper electrical functioning, the AC system won’t be able to operate correctly.
3. Faulty compressor: The heart of the AC system, responsible for pressurising and circulating the refrigerant. If the compressor fails due to mechanical failure, leaks, or wear and tear, the AC system won’t be able to cool the air effectively.
4. Low refrigerant: Essential for the AC system to function correctly. If there’s a leak in the system or the refrigerant levels are low, the AC won’t be able to produce cold air. Identifying and fixing the source of the leak and recharging the refrigerant is necessary to restore proper AC operation.
5. Cabin air filter: Helps keep the air inside the vehicle clean by trapping dust, pollen, and other airborne particles. If the filter becomes clogged or dirty, it can restrict airflow, reducing the efficiency of the AC system and potentially causing it to stop working altogether.
6. Damaged compressor clutch: If it becomes damaged or worn out, it may fail to engage appropriately, preventing the compressor from functioning correctly and leading to AC failure.
7. Blown fuse: Relies on various fuses to protect its components from electrical surges or overloads. If a fuse related to the AC system blows, it can disrupt power flow to critical features like the compressor or blower motor, resulting in AC malfunction.
8. Damaged evaporator: Responsible for absorbing heat from the air inside the vehicle, cooling it down before the blower sends it into the cabin. If the evaporator becomes damaged due to corrosion, leaks, or other issues, it can compromise the cooling efficiency of the AC system and cause it to stop working.
9. Expansion valve: Regulates refrigerant flow into the evaporator, controlling the temperature and pressure of the refrigerant as it enters the system. If the expansion valve becomes faulty or clogged, it can disrupt the refrigerant flow, leading to poor cooling performance or AC failure.

So, how much does it cost to fix a car’s AC compressor?

In many situations, the AC compressor lasts the whole vehicle life without requiring replacement, although failure is more likely after 150,000km. On average, you can expect your AC compressor replacement to cost between $800 and $1,200, sometimes even more, depending on the make and model of the car you drive.

Therefore, an important aspect is that your AC won’t function if the compressor is broken. Contact us now for our team of expert’s opinions on any issue or damage your vehicle faces.