One of the most common air conditioning problems we hear about this time of year are issues with ice forming on the outdoor unit, line sets, and evaporator coil (indoor coil). Most people only notice the ice on the outdoor unit since it is visible to the homeowner; however, ice forms first on the evaporator coil. I have listed a few common reasons why a system may form ice and a few things that you can do to prevent this from happening to you.

4 Reasons Why Your System May Be Freezing Up

1. Restricted air flow:  Many homeowners overlook the importance of keeping a clean filter. Maintaining proper airflow across the evaporator coil is crucial to keep your unit running properly. When filters become clogged or dirty, it greatly reduces the air flow needed to prevent the formation of ice on the evaporator coil. The last place that ice forms is on the outdoor condensing coil.

2. Refrigerant: When the system is low on Freon it can cause it to form ice on the evaporator and condenser coils and line sets. If it is low on Freon, it could be an indication that the system was improperly charged or is leaking Freon. A properly trained technician should perform a leak check to identify the source of the leak.

3. Mechanical failure:  There are many components of your heat pump such as fans, relays, or valves that may fail and cause problems with the flow of refrigerant. A qualified technician will be able to diagnose the failure and give homeowners options for repair or replacement.

4. Temperature:  When temperatures are below 65 degrees outside and your AC is running, ice could form on your unit. Having your thermostat set too low can cause your air conditioner to run constantly, which can eventually drop the temperature of your evaporator coil to below freezing.

If you find your system frozen, the first thing you should do is turn the system off on the thermostat to allow it to thaw completely. The second thing you should do is check your filters. To prevent ice from forming you should replace your filters every 30 days or as needed. Next, make sure your thermostat is not set too low. We recommend not setting it below 70 degrees. If your system is still freezing up, call Davis Heating & AC and we will send out one of our qualified service technicians.