If your central air conditioner does not seem to be cooling your home, you may have already checked the thermostat and changed the filter to see if you could fix the issue. However, if your attempts have met with failure, there may be an issue that you cannot deal with yourself. Below are a few possible reasons why your central air conditioner is no longer blowing cool air that should be attended to by a professional.

Refrigerant Is Low

One reason why your A/C unit may not be blowing cool air is that the refrigerant is low. If there is not enough to fully circulate throughout the unit's condenser, your air conditioner will not have the ability to fully cool the air before it flows through your vents and into your house.

However, simply filling your air conditioner with refrigerant will most likely not fix the issue. If your unit is low, there is probably a leak or crack in the line.

You will need an HVAC professional to test the system, repair the line, and then fill the unit back up with refrigerant. Do not attempt to perform this repair yourself, as it must be done by someone with the proper certification to handle AC refrigerant.

Fan Belt Is Broken

Another possible problem with your AC unit could be a broken belt. The belt inside your air conditioner connects the compressor to the fan. While the compressor is busy cooling the air flowing through the unit, the belt allows it to also turn the fan so that the cooled air is forced into your home's ductwork and through your vents.

If your fan belt is broken, however, the cold air will sit inside the unit and cool it too much. You may notice that your air conditioner is frozen up, with ice forming on the interior and exterior.

However, a unit that frequently freezes up could also be a sign that your compressor is going bad. You will need to have an air conditioning repair technician take a look so they can determine the actual cause.

If you suspect that any one of the problems discussed above is the reason why your air conditioner is no longer cooling your home, you will need to have someone take a look at it. Contact an air conditioning repair contractor to have them inspect the unit and discuss your options for fixing the issue.