Why Does My AC Freeze in the Summer?

Your air conditioner is a hard working piece of equipment in the summer time. Let me explain this common problem and what occurs when your AC decides to freeze on an 85+ degree day.

The evaporator coil is the component of a central AC unit that actually freezes. This component of the air conditioner transfers (evaporates) heat from the inside to the outside of your home.

There are two main reasons why your evaporator coil may freeze, the first and most
common one is airflow restriction, which can occur if your filter is dirty, or your evaporator coil is dirty or damaged, or your air ducts are not properly functioning and air leakage from your attic or crawl space ducts are vacuuming insulation into your system, thereby restricting airflow to the point where the air is so severely blocked that your coil freezes.or even a mismatched system where the outside unit is too large for the inside unit (evaporator coil).

The second reason is insufficient refrigerant, (that’s the lifeblood of your AC system!) which can occur if there is a refrigerant leak, causing the refrigerant levels to become low.

Either way, the end effect is that the air conditioner’s evaporator coil cannot operate to properly transfer heat, and in essence over cools itself. The net effect of this supercooling is condensation, (that’s water formation) then, finally ice forms from that condensation as it cools below the freezing point. Yep, your AC just transformed into an old­ school icebox.