What Causes A/C Coils To Freeze

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Frozen coils on your air conditioner can be caused by a variety of system failures, which can make them difficult to diagnose. Many of these issues can be quickly fixed by a San Marcos HVAC professional, but if left unattended they can wreak havoc on your air conditioner. In order to keep your A/C running at peak efficiency through the summer, keep an eye out for these few problems that can cause frozen coils.

Thermostats Malfunctions

Properly functioning thermostats detect the temperature in the area that needs to be cooled, and indicate how hard the air conditioner has to work to cool that area. If the thermostat malfunctions and detects the wrong temperature, this can cause your A/C to run too hard for long periods of time. If your A/C runs for too long it can cause the coils to freeze. If you notice that your A/C is running too cold, or for long periods, this could be the issue.

Refrigerant Leaks

If your air conditioner has a refrigerant leak, it’s likely that the refrigerant level will be lower than recommended. If the refrigerant gets lows, the pressure in the copper lines that carry it will also lower. Liquid refrigerant can then run into these lines and freeze the moisture inside, causing frost to form on the lines and potentially freeze them. To learn more about the symptoms of a refrigerant leak, check out our article Is Your A/C Low on Refrigerant?

Insufficient Fan Speed

The fans in your air conditioner can also contribute to frozen coils. If a fan has a broken or slow motor that prevents it from running at the appropriate speed, then air cannot get through the A/C system. Dirty fan blades can also impede air flow. If air is unable to circulate through the system, this can cause your A/C coils to freeze.

Drainage Issues

Your air conditioner or HVAC unit uses condensate lines to drain excess moisture that results from humidity. If one of the lines gets clogged and prevents the excess water from draining properly, it can cause the standing water to freeze all the way back to the evaporator coil. Ice can also block the drain itself, which can make drainage problems worse. It’s a good idea to check your drain pipe during the hotter months so that if a frozen drain is an issue, it can be repaired quickly.

Dirty Filters

Dirty filters can also result in frozen coils. Like broken fans, dirty filters can prevent air from flowing adequately throughout the system. If air doesn’t circulate properly, the coils in the A/C unit can get too cold, and end up freezing. Dirty filters can also contribute to extra wear on your compressor, lowering the life expectancy of your A/C unit. It’s a good idea to clean your filter monthly in order to prevent this.

For more information on frozen A/C coils, or to speak to an HVAC professional, contact AirOne Heating and Air Conditioning in San Marcos, TX.