Why is my A/C freezing up?

Air conditioning units have been working overtime during an especially hot summer season in the Charlotte area. Humid air that brings rain and thunderstorms, and temperatures consistently hitting the 90s, combine to take their toll on A/C operation. And one of the most unfortunate results can come out of nowhere it seems: your unit freezes up. MTB Mechanical shares three reasons why this might be happening – and what you can do about it. 

  1. Obstructed air flow. This is often the culprit of an A/C unit malfunction. If the flow inside your home is blocked, even partially, less air is moving through your system, which can cause condensate on the evaporator coil to freeze. Obstructions can range from objects covering air registers and returns, to dirty air filters that need changing. Fortunately, when these issues are addressed, air can again flow as it should. Need help remembering when to regularly change your filters? Sign up for our free filter reminders
  1. Low or leaking refrigerant. When the refrigerant in your A/C unit gets low, it forces the system to try to expand and fill the missing space. The pressure drops – and along with it, the temperature. The moisture inside the unit freezes as it comes in contact with the evaporator coil. If this is the case, an HVAC professional is needed to check for leaks and fill the refrigerant to proper operating levels.  
  1. Mechanical failure. A range of essential mechanical malfunctions can cause an air conditioning unit to freeze up. There may be a clogged filter dryer. The blower may not be running properly or has been damaged. Or there may be a crimp or obstruction in the refrigerant lines. 

One thing is for certain: when your A/C unit freezes up in the heat of summer, you need the help of a pro. Contact MTB for assistance in finding the root of your problem, and the expert service you need to get your system back to normal, for a cool and comfortable home. Schedule an appointment online or call us at 704-321-9250.