What’s Wrong With My Car’s Air Conditioning?

A car a/c that doesn’t work properly on a hot day is a nightmare. If your a/c blows hot air or the cooling performance has gone down, you have a problem. Here are some common car a/c problems to help you understand what you are up against.

Refrigerant Leak

For optimal cooling, your a/c must have refrigerant at the right pressure. If the refrigerant has leaked, the unit will not cool or the cooling efficiency will decrease. As cars get older, leaks can develop in the pipes and hoses of the air-conditioning system, especially at the joints.

Your mechanic will be able to measure the refrigerant pressure and ascertain whether there is a leak. Leaks are sometimes difficult to find because the holes can be very tiny. To find the leaks, the refrigerant is recharged with a dye added. Small leaks may show up only after using the a/c for a while. A second garage visit may become necessary.

Some components like the evaporator are under the dashboard and leaks here are harder to find and fix. The dashboard panel may need to be removed to fix the issue. System performance should be restored once the leaks are closed and the refrigerant is refilled to the right pressure.

Condenser Problems

The refrigerant gas is compressed to a high pressure by the compressor from where it flows to the condenser. It is located behind the front grill of your car. The condenser is a heat exchanger and it cools the hot refrigerant gas with the help of the air flowing through the grill. Sometimes, road debris or dirt can block airflow to the condenser fins and prevent heat exchange. Cooling will be impaired if the a/c operates with overheated refrigerant. This is one of the reasons for warm air flowing through the vents.

If something is blocking the air flowing to the condenser, you may be able to check and remove it through the front grill. Condensers can also get damaged due to road debris flying in through the grill. A damaged condenser will need to be replaced.

Cooling Fan Problems

The cooling fan is responsible for maintaining the airflow through the condenser. If the fan does not operate, the refrigerant will not cool. Electrical problems or blown fuses are the common causes of cooling fan failure. Like condensers, cooling fans can also be damaged by road debris. If the fins are broken or cracked, you may need a new fan.

Compressor Problems

A faulty compressor will not be able to circulate refrigerant at the right pressure and your a/c will not function. Keeping the a/c off for extended periods can cause compressor problems in some cases. It’s better to operate your a/c at least once in a month irrespective of the season.

Electrical Problems

Electrical problems can cause a/c malfunction. This is not uncommon in modern cars, which have complex electronic systems. Problems can also be caused due to damaged or broken wiring, short circuits, blown fuses or faulty sensors.

Intermittent Problems

A car a/c that fails intermittently is a headache because you can’t rely on it. It can also be difficult to diagnose. If the cooling is fine initially and the system blows hot and cold air in alternate cycles, the evaporator is probably freezing up. Intermittent problems can also be due to electrical faults.

If you have an intermittent problem, the best way to help your mechanic find the fault is to observe and note down the conditions in which it occurs. Here’s a list.

1. How often does the a/c fail?
2. How much time after you start driving does the system fail?
3. What were the control panel settings when the system failed?
4. Are there any strange sounds?
5. Is the air warm only in some vents?
6. Does the problem occur only when you drive slowly or fast?
7. Does the control panel malfunction?
8. Is the heater working fine?

Dirt And Mould Growth

Dust and dirt can accumulate in the ducts, evaporator and air vents. The warm and moist conditions within the air-conditioning system are ideal for mould growth. Getting the a/c serviced every two years will help keep this in check. If you get a musty odour when you start the a/c, it’s time to get it cleaned. Ignoring this can cause serious health problems.

Complete our short booking form if you need your car air conditioning serviced, repaired or refilled. We will assign your requirement to a respected garage in your area. Our network garage will contact you and you can get your car serviced conveniently at a very competitive rate. We also offer a pick up and drop off service or if you need to stay mobile you can book a courtesy car, both services are totally free of charge.

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