What Causes a Frosty Heat Pump and Should I Be Worried?

Even though spring is here, thanks to unusual weather conditions over the last few months, the Glenview, Illinois area will still flirt with freezing temperatures this week before the official warm up begins. Ice on the heat pump might be a common sight when it’s snowing or when there is freezing rain. However, ice buildup otherwise could mean trouble. Minor frost formation isn’t a problem for most modern heat pumps, but when ice starts to build up, it’s a good idea to contact your technician right away to prevent further problems.

Why It Happens

Water vapor is present in the air around you, even when it’s cold and dry outside. Your heat pump is tasked with extracting heat from the cold air, and it also condenses that water vapor into liquid form. As temperatures approach the freezing point, there’s a good chance that the condensed water will freeze, creating that telltale frost over the coils on your outdoor unit.

Need a good idea of when this might happen? Pay close attention when outdoor air temperatures hover around 20 to 40 degrees with a relative humidity level of 70 percent or higher.

When Should You Worry?

A little frost isn’t anything to worry about. Your heat pump features a defrost cycle that uses the unit’s own heat transferring abilities to melt away minor frost. On the other hand, finding your unit encased in a thick sheet of ice is definitely a problem. Major frost and ice buildup block the coils from receiving proper airflow. This will prevent the unit from heating your home effectively and can even shorten its lifespan.

This can happen because of a low refrigerant charge. A stuck reversing valve, a defective defrost thermostat sensor or relay, or a broken outdoor fan motor, are also possible causes. Even something as simple as leaves and other debris blocking the outdoor unit can cause this problem.

What Can You Do About It?

A little maintenance goes a long way toward keeping your heat pump frost-free. That includes keeping up with routine inspections and repairs. For more information about handling a frosty heat pump, contact the pros at Carefree Comfort, Inc. by calling 847-388-0115.

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