If you walk into a warm house and check your air conditioner to find it coated in ice, you might be taken by surprise. However, it's fairly common for an AC to freeze for a number of reasons. A primary reason is when there is a refrigerant leak. However, low airflow can also cause the coils to freeze. Here are possible reasons for low airflow that leads to coil freezing and the AC repairs that could be needed.
Things That Reduce Airflow In Your AC
A common cause of poor airflow is a filter that's covered in a thick layer of dust. When you see ice on your AC coils, check the filter first. Change it if it's covered in dust, and that could quickly solve the problem.
If the blower fan isn't putting out enough air, that can lead to low or no airflow over the coils. The lack of airflow then causes the coils to slowly freeze over. A blower fan is operated by a motor, and the motor gets a boost of power from the capacitor. If the blower motor or its capacitor goes bad, the blower fan won't spin and blow air.
Excess dust is another problem that leads to reduced airflow. This might happen if the blower blades are coated in dust or if dust and grime affect the motor or cover the coils. When the filter is coated in dust, some of that dust can get sucked inside the air handler and cause problems with the blower system that leads to the coils icing over.
AC Repairs That Improve Airflow
The first step is to turn off your air conditioner and run the fan only so the ice will melt. This is necessary before your AC repair technician can work on the equipment. The technician can test the various components of the blower system to see if the motor or capacitor is bad. If so, they can be replaced with new parts.
There could also be a problem with the electrical supply to the motor and capacitor. In that case, the AC repair technician might need to check wiring or the power supply to the air handler. The technician may also take the time to remove the blower cage along with the motor so the cage can be cleaned thoroughly before replacing it.
Once the ice has melted from the coils, the technician might go ahead and clean them too. With the blower system working properly and all the dust cleared out of the way, there should be enough air blowing over the clean coils that your AC starts chilling your house again without freezing over.