The Cold, Hard Truth About Icy Buildup

While some frost or ice on the outdoor coils of a heat pump is part of normal operation, repeated ice-ups or a thick layer that won’t defrost on its own could signal serious issues with your unit.

If this problem is not addressed in a timely manner, it could lead to costly damage, if not total system breakdown.

“Why does this happen in the summer? It’s HOT outside!”

We agree! It doesn’t seem to make sense at first glance. However, as your heat pump cools your home by running outside air over coils filled with a cooled refrigerant, condensation builds up. If the coils get too cold, that condensation can freeze into ice, leading to problematic buildup. This is not a problem you should attempt to investigate or remedy yourself. Your One Hour Heating and Air professionals can conduct a thorough system inspection to pinpoint the exact nature of the icing problem and save you time and money in unnecessary repairs or expensive DIY mistakes.

Some of the Most Common Sources of Outdoor Icing on a Heat Pump Are:

  • Low refrigerant levels.
  • Malfunctioning defrost controls, defrost thermostats, defrost relays or sensors
  • A reverse valve that sticks
  • Damaged or malfunctioning outdoor fan motors
  • Improper installation (leading to poor airflow)

As you can see, there are several reasons for possible ice build-up on your heat pump and all of them require an experienced, expert response. When you notice this issue, the first thing you should do is shut your heat pump down completely. There are some troubleshooting steps you can then take before giving One Hour Heating and Air a call:

  • Air filter: check to be sure your system’s filter is not dirty, damaged or clogged. One inexpensive maintenance step is replacing these filters (even if the unit is not totally iced over).
  • Coils: Make sure natural debris (grass, sticks, leaves, dirt, etc.) and trash have not built up around the coils blocking airflow. If it has, clean it away immediately.
  • Gutters: While your home’s gutters aren’t directly related to your heat pump system, gutters that overflow might be dumping water into your unit every time it rains. Make sure any overhead gutters are clean and collecting water properly.
  • Vents and Registers: As with outdoor coils, you will want to make sure indoor vents and registers are not blocked by furniture, boxes, piles of magazines, or other objects.
  • Run Defrost Cycle: Both older and new heat pump models feature defrost options. It essentially works by reversing the valve to air conditioning mode, which turns the outdoor evaporator into a condenser by switching off the outdoor fan. This, in turn, warms the high-pressure refrigerant which moves through and warms the outdoor coil, melting the ice.
  • Let the Sunshine In: If your model does not have a defrost feature, or it is old and doesn’t function well, simply turn off your system and let the sun do its thing to melt the ice. Granted, this option means you will be without cool air in your home for the time it takes the icy buildup to melt away. Overnight hours, when the sun is not blazing hot on your home but outside air is still warm, is the best time to explore this option.

Don’t risk damaging your heat pump if it freezes completely or develops icy buildup. One Hour Heating and Air will send a highly-trained, licensed and insured technician to your home to find the most effective and cost-efficient solution to your comfort system’s particular issue. Our professionals are your go-to HVAC team in Charlotte and the surrounding area, including Indian Trail, Concord, and Mooresville.

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Call our 24/7 customer service line today (704) 703-4220.