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While the push of a button is all it takes to turn the air conditioner on in your car, there are many different components working in tandem behind the scenes to produce the cool air we've come to rely upon, and any one of these may cause the system to not work properly. Fortunately, the air conditioning in cars made today are usually highly reliable systems with very little problems occurring, however, the most common difficulties are either no cool air or simply not enough cool air flowing from the vents.
No Cold Air
No cold or cool air at all coming from the air conditioner's vents may mean any one of the following problems:
- A blown fuse
- A broken drive belt
- A clog in the expansion valve
- A clogged refrigerant line
- A clogged receiver-drier line
- An existing defect in the expansion valve
- A slow leak in the hoses or seals
- A loose drive belt
Not Enough Cold Air
An insufficient flow of cool air coming from the A/C may signal another set of problems, including:
- A clogged condenser or evaporator
- A loose drive belt
- A low refrigerant charge
- A partially clogged expansion valve
- A partially clogged filter
- A problem with the compressor clutch slipping
- A slow leak somewhere in the system, such as in the hoses or seals
While it is completely normal for some refrigerant to leak from a car's air conditioning system, larger leaks may indicate a bigger problem with the compressor's seal or damage to one of the components.
Caring for Your Car's Air Conditioner
Although most repairs for air conditioning systems in cars will require special tools and equipment that many of us do not own, there are still several things you can do to keep your car's A/C running at its full capacity. Regular maintenance checks, according to the recommendations in your car's owner's manual, are important as the system contains many moving parts and components that must be checked for damage or disrepair.
Many newer makes and models of cars come equipped with filters within the duct portion of the air conditioner that are in place to trap dust and pollen before it reaches the air in the car. Although these may be rather beneficial for those people who suffer from allergies, depending on where you live and the air quality and pollution levels, the filters may fill up quickly and cause a reduction in airflow.
While there may still be enough refrigerant in place to cool the air, the clogged filter will impede the flow, making it too weak to cool down the inside of the vehicle. Directions for changing this filter and where to purchase new ones should also be in the owner's manual.
Even air conditioning systems without this special filter in place can experience reduced airflow because of trapped dirt, pollen, and moisture that may eventually turn to mold, further aggravating allergies.
If there is a musty odor coming from the A/C vents just after turning the system on, this may indicate the presence of mold which could be blocking the system's evaporator. The air might feel cool, but the flow won't be strong enough to cool off the entire car. A mechanic will be able to remove the parts necessary to clean, such as those leading to the evaporator, with certain chemicals needed to dissolve the build-up.
Even if you live in a cold climate and don't need to use your car's air conditioner very often, many mechanics recommend running the system for at least ten minutes per month to keep the moving parts within the compressor properly lubricated. The compressor is also used in many types of cars when the defroster is used, so you may not have to actually run the air conditioner at all.
