Why An Air Conditioner Freezes And The Repairs That Might Be Necessary To Get Your AC Working

Your air conditioner is able to cool your home because of a balance between cold refrigerant flowing through the lines and warm air from your home blowing over the coils. If either of these processes are disrupted, then your air conditioner could freeze over because the refrigerant in the lines gets too cold. It may seem odd for your AC to freeze when it's hot outside, but a frozen air conditioner is a common problem, and it can often be prevented by keeping your AC coils and filter clean. Here's a closer look at what can cause this to happen and the repairs your AC could need.

Problems With the Refrigerant

The refrigerant in your air conditioning system has to be kept at the right level so the pressure is in the right range. If the pressure of the refrigerant is too low, problems can occur. Pressure changes cause the refrigerant to change from a liquid to a gas and back to a liquid again as it circulates through your system. If the pressure is too low, that causes the coils to get too cold and moisture from the air freezes on the coils. Once ice starts collecting, it sets off a chain reaction that accelerates the ice buildup.

The refrigerant level isn't supposed to change, so if it's low, that means there is a leak in your system. An air conditioning repair service has to find the leak and repair it. Once that's done, refrigerant is filled to the correct pressure and the freezing problem is solved.

Problems With the Airflow

If the refrigerant level is fine but the warm airflow over the coils is reduced, the temperature of the coils gets colder and the lines start to freeze. This happens in a few ways. There might be lower airflow due to a restriction caused by a clogged filter or the airflow might be reduced because the blower fan isn't blowing enough air. The problem might also be due to a blanket of dust coating the coils that keeps air from contacting the cold coils.

One thing to try when you notice your AC freezing is to check the filter. If it's caked with dust, change it and see if the AC starts working again once the ice has thawed. If the filter seems clean, call an AC repair service for help so the source of the problem can be identified and repaired. This might involve working on the blower or the blower motor. It's also possible that cleaning off the coils could solve the problem.

When you call an air conditioning repair service, let them know your AC is frozen. They can then advise you on what to do to prepare for your service call. You might be instructed to shut down the AC but leave the fan running so the ice thaws out quicker and the technician can get to work on the problem faster.