Why would my air conditioner freeze up in the middle of summer?
A frozen air conditioner in the middle of summer is really common. But it is a sign that all is not well.
Several issues could be at fault.
Not enough airflow is a common cause. Anything that restricts the flow of air through the system will cause the the temperature of the evaporator coil to drop below freezing. The moisture in the air will then freeze onto the coil which will further limit the ability of the system to move heat out of the home. That air flow is what carries off the cooler air for your comfort and enjoyment. Without the flow, no cold air and and coil will start to built up ice. Too small or collapsed ducts, dirty air filters, bad blower motors or lots of dirt on the evaporator coil can all be a cause of ice the evaporator coil of your air conditioner.
Problems With The System’s Refrigeration. Refrigerant leaks or low levels of refrigerant can cause pressure drops in the air conditioner’s evaporator coil, which will allow moisture in the air to freeze and accumulate on the coil.
You are running the air conditioner when it is cold outside: Most outdoor air conditioning units do not function well in temperatures below 60 degrees F. If night-time temperatures are too low, the system will not operate properly and freeze-ups can occur.
What To Do When Your Air Conditioner Freezes Up
Panic! No really the buildup of ice and frost is a sure sign that your air conditioner is not operating properly (it is usually one of our prime suspects, dirty filters, poor air flow, or low refrigerant levels) . If you notice a decline in your system’s cooling capacity, ice build-up should be the first thing you suspect. Air conditioner freeze-ups should be addressed immediately; continued ice accumulation can cause permanent damage to your a/c unit.
The first thing you should do once you notice your air conditioner is frozen is to turn it off and let it defrost completely. Once it has defrosted, check the airflow. Clean or replace dirty filters or remove any visible dirt or obstructions; in some cases, this could be all that is needed. If your icing problem is due to drops in the outdoor air temperature, be sure to turn your air conditioner off when it looks like it is going to be cold at night.
More serious airflow and refrigeration problems require professional intervention like Boer Brothers for instance.