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Ice on the AC Coil: Is That Normal?

    frost-on-windowCustomers trust our HVAC technicians to give them expert advice when it comes to their air conditioning equipment. A question we sometimes hear is whether it’s normal for ice to form on the indoor coil of an air conditioning system while it’s running during summer.

    We understand why people might believe a frosty AC is normal. They feel chilled air coming from the vents, and what’s more natural than to have ice involved in the process? One of the ways to rig up a simple cooling system is to place a bowl of ice in front of a fan; wouldn’t it make sense for an air conditioner to work in a similar fashion?

    The answer is: no it isn’t. Ice on an air conditioner coil is a symptom of a problem with an air conditioner—possibly a major one—that requires air conditioning repair.

    Air Conditioners Do Not Use Freezing to Cool a Home

    At no point in the cooling process does an air conditioner use ice or frost, and it shouldn’t be a byproduct of the process either. An air conditioner is a type of heat pump, which means it pumps heat from one location to another, in this case removing heat from inside a home and moving it outside. It does this through the circulation of a chemical refrigerant blend that evaporates and condenses in a heat exchange cycle. Although the refrigerant in the indoor evaporator coil is extremely cold, it should not trigger the creation of ice because it warms up as it absorbs heat from the air.

    Why You Might See Ice on the Indoor Coil

    There are a few possible causes of the “frozen coil” problem:

    • The air filter for the HVAC system is clogged. This is one of the reasons to keep current with changing the filter (every 1 to 3 months). If insufficient warm air is drawn over the coil, it will remain too cold and moisture will start to freeze along it.
    • The coil may be dirty (which could be from a clogged filter as well). Dirt serves as an insulating later over the coil, restricting its ability to absorb heat. This leaves the refrigerant too cold, and will again start to cause moisture to freeze along the coil.
    • The AC may have a refrigerant leak. This is the most serious problem, since a drop in refrigerant level changes pressure throughout the system and will damage the compressor. The reduced refrigerant level hinders heat absorption on the coil, leaving the remaining refrigerant too cold … and the same moisture freeze will start.

    Ice on a coil will only continue to grow, because the ice prevents heat absorption. But you don’t want to try to scrape off the ice to fix the trouble. Not only will this fail to solve the root problem, but it might damage the coil. Call HVAC professional for repairs.

    Calling us for air conditioning repairs in Roswell, GA is the fastest way to see any troubles with your home cooling system are solved—fast and right!

    We are offering 10% off repairs or $150 off replacement systems for members of the military and senior citizens. Contact us for more details.

    Comfort Zone Heating & Cooling serves Cummings, GA and throughout North Atlanta. Call our customer service specialists at 770-213-COOL (2665) and let us know how we can help.