Are Your AC Coils Frosted?

And no, that’s not an attempt to start an argument. A central air conditioning unit’s coils can become covered in ice when a couple of things happen: The temperature of the refrigerant dips below the freezing point, and the humidity on the atmosphere freezes onto the surface of the coils.

Much like a frozen fuel line in a car would prevent the automobile from operating correctly, frozen coils can have a similar effect on air conditioning units – in this case, placing undue stress on the compressor, which could then experience failure. Before calling a qualified professional to repair the unit, first turn it off and thaw the coils. Here’s how, courtesy of SFGate.com:

While it may look to speed up the thawing process by taking away large sections of ice by hand, that’s an easy way to damage the cooling fins and coils in the AC unit. Not just because a tool could miss its mark, but because the ice fuses to the surface of these parts – which means that pulling it away manually could break coolant lines or warp the fins. The alternative: With the AC unit switched off, run the blower fan, which will push warm air across the ice, eventually resulting in a safer thawing process.

As for trying to remedy what might have caused the coils to ice up in the first place, check that air flow isn’t blocked. This can happen when filters become clogged or when there is not enough return air. And try not to run the AC unit when the outside temperature fails to reach 60 degrees.

Ask you service professional to check the level of refrigerant in the unit; low levels can also cause frosting of the coils. Because refrigerant can freeze on the skin in an instant, it’s best to let a pro handle this step of the process.

And if the AC unit does not shut off once the inside temperature has cooled to the level on your thermostat, it could be the result of an electrical contactor that needs to be replaced—another task that should be reserved for a qualified professional.

More questions about frosted coils? Contact AC World today!