During the warmer months (or all year long, if you’re lucky enough to live somewhere tropical), cooling is a crucial aspect of owning a home or business. While today’s air conditioners are designed to last several years, there are a number of common problems that can and do occur. Some problems are noticeable right away, and some require technical expertise to assess. Some are solved easily (such as replacing filters or removing obstructions from ducts), while others require more advanced AC service.
You may have noticed that your air conditioner is not performing as it should—and you’re wondering what the problem could be. Or perhaps you want to make sure your system is ready to go as Summer draws near. To give you a head start on the process, we’ve compiled a list of some of the most common problems we find during maintenance checks and house calls.
Fuses — Like any hard-working appliance, air conditioners can overheat. As protection against this, fuses located in the unit’s evaporator will blow out when the system gets too hot, thereby protecting the unit against serious damage. Sometimes an air conditioner has stopped working due to a blown fuse—although there may be other problems that caused the unit to overheat.
Contactors — These components make an electrical connection to various parts of the unit, telling it when to kick in. If these contactors are worn, bent or frayed, the current may not able to start the motor and compressor. New contactors, properly installed, can get the unit up and running, and prevent similar episodes in the future.
Capacitors — These cylindrical parts make sure that the system runs at a constant rate of speed. There are two types of capacitors—a start capacitor and a run capacitor—that allow the compressor to kick in, reach the required speed, and stay there. What happens when either capacitor breaks down? The unit will not be able start or run properly.
Filters — Air conditioners use filters to make sure the air coming through to the unit is clean. It’s important to replace AC filters regularly, either DIY or by a professional AC service. An old, dirty or clogged filter will prevent air from properly flowing into the unit, which eventually causes it to freeze and malfunction.
Thermostat — During some house calls, the thermostat is found to be switched off or improperly programmed. It’s always a good idea to check your thermostat first, before calling a professional for help. Mechanical problems with the thermostat can also occur, leading to necessary repairs or a replacement.
Compressor — Your AC unit relies on a compressor loaded with a proper amount of refrigerant. Sometimes the refrigerant leaks or runs out, causing excessive heat in the compressor, which ultimately leads to mechanical failure. On the other hand, too much refrigerant will prevent the compressor from circulating the liquid efficiently and doing its job. Checking the level of refrigerant in the compressor is a routine part of troubleshooting.
Drainage problems — Because AC units generate condensation, they need a drainage system comprised of a drain line and drain pan. Due to the unit’s exposure to the elements, it’s possible for the drain line to become blocked with grime or dirt. When this happens, the drain pan spills over and the unit can sustain water damage, leading to mechanical failure.
Coils — Central AC systems have two types of coil: A condenser coil in the external unit, and an evaporator coil which is sometimes within the unit and sometimes in another part of the building. Both types of coil are needed for the system to work properly, and are subject to inspection. They can get dirty, and can sometimes crack. Routine AC service checks will ensure that your unit’s coils are in good shape.
Refrigerant leak — The liquid refrigerant in your AC unit must be contained and properly circulated at all times. Leaks sometimes occur in various places throughout the unit. If refrigerant is leaking in one of the coils, the problem is serious and it may be necessary to replace the system. Leaks occurring in other places can usually be repaired without much trouble by a qualified technician.
We hope you’ve found this list of common problems with AC units to be helpful! We’re here to share information and help you find solutions. Please feel free to leave your comments below, or contact us with any specific questions you may have.