How to Prevent an Air Conditioner from Freezing

How to Prevent an Air Conditioner from Freezing

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Summertime air conditioning problems can often include frozen air conditioning units. If your air conditioner is freezing up, your household may be stuck without cooling for hours or even longer. Prevent discomfort and keep your cooling unit thawed and free of ice this season with these tips from Estes Services.

Why Is My Air Conditioner Freezing Up?

When you hear someone mention AC problems involving a frozen air conditioner, it doesn’t mean the entire outdoor heat pump or AC condensing unit is encased in ice. It’s actually the evaporator coils that can freeze up, and this component sits within the indoor portion of your split air conditioner system in either an air handler or furnace unit.

Evaporator coils hold refrigerant that absorbs heat from the air as air passes over the coils when circulating through the cooling system. Condensation can form as air temperature drops, pulling some humidity out of the air. If various issues are present that cause evaporator coils to freeze, this condensation can form light layers of frost to heavy, thick ice on the surface of the coil.

Here are the reasons behind a frozen AC unit:

  • Low refrigerant: Insufficient refrigerant causes the evaporator coil to become very cold. This can cause condensation to freeze along the coils.
  • Low air flow: A dirty air filter, closed supply vents, or a slow blower fan are issues that cause insufficient airflow through the system. If there isn’t enough hot, humid air flowing through to the evaporator coil, the refrigerant within the coil is unable to gather enough heat to prevent the coil from dropping in temperature.
  • Condensate drain blockage: If the condensate drain pan or drain line malfunctions or suffers a clog, condensation will not properly leave the interior of the air conditioning equipment. Moisture backs up in the system causing more condensation to remain on the evaporator coil, which may freeze.

What to Do When an AC Unit Freezes Up

If your evaporator coils freeze this summer, don’t worry – this is one of the most common AC problems and it can sometimes be fixed with some DIY effort. Follow these steps to unfreeze your unit:

  1. Shut off the air conditioning system – you do not want to continue running the air conditioner when the coils are frozen, as doing so can severely damage the compressor and other components.
  2. Check the condensate drain line and drip line for clogs, removing any if found with a wet/dry vacuum.
  3. At the thermostat, switch the system fan to ON mode instead of AUTO. This allows the blower to run continuously in absence of a cooling cycle, which will force warm air over the coils and help them thaw faster.
  4. Check the air filter, and replace it if it is filled with debris and contaminants. 
  5. Check all rooms of your home to make sure supply vents are open and unblocked.

Once all of the ice has melted from your evaporator coils, you may start the cooling system once more. If the coils continue to freeze up, call your trusted HVAC professional to repair these AC problems.

How to Prevent a Frozen Air Conditioner

Reduce the chances of air conditioner problems in your home this summer by doing the following to protect your AC from freezing:

  • Have your air conditioner undergo a professional maintenance tune up prior to the start of cooling season.
  • Check the air filter regularly and replace as needed. Check it about every month, as replacement may be needed sooner than expected due to heavy summer system use.
  • Inspect your condensate drain pan and drain line for clogs every week.
  • Always keep supply vents open in your home. Don’t be tempted to close them in unused areas for energy savings, as this myth actually causes more harm than good.

Contact Estes Services for AC Repair Services

When you experience AC problems like a frozen air conditioner in your Atlanta home, do you know who to call? Trust Estes Services with your family’s comfort. Our technicians find the source of coil freezing and correct it so you don’t have to sweat through repeated periods without cooling. Contact us today for AC repairs.