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What Causes a Heat Pump to Freeze?

Your central heater and air conditioner both rely on a heat pump to perform the heat transfer that both heats and cools your home. While it might seem hard to believe, your heat pump could actually freeze over, both during the hottest days of summer when running your air conditioner at full blast or the coldest nights of winter when it’s working overtime to generate heat. This is especially true during a deep freeze like we’re experiencing right now: a frozen heat pump not only won’t work properly but also is a warning sign that there are other big problems with your heating and air conditioning system that need to be rectified.

Ice on Coils

It’s not uncommon for a thin layer of frost to form on your coils, but a large buildup of ice is not normal and points to one of these larger problems. Normally heat pumps have automatic controls that put them into defrost mode when too much ice builds up, but when they malfunction a full-fledged freeze can occur, leaving you out in the cold during deep freezes like the one we’re currently experiencing. If your coils have frozen over, it’s strongly advised you have a St. Charles heating repairs expert come to your home and diagnose whether the automatic controls are the issue, or if there’s something even deeper-rooted in your system that needs to be repaired.

Obstructed Air Flow

The coils in your heat pump are designed to function with a certain amount of airflow at all times. If this airflow is restricted too heavily, you could experience a pretty significant problem. Restrictions can be caused by all sorts of issues. Some easy things to check are the condition of your air filter (replace it if it’s dirty or past its suggested lifespan) and the area around both your indoor and outdoor unit. Outdoor units can become clogged by things like leaves, grass, and even snow, so clear any of this away from your outdoor unit to improve airflow. Make sure your indoor unit isn’t blocked by anything like carpet, furniture, or large boxes that may have been placed in the way of your intake vent.

Water Condensation

Water can condense in your outdoor unit, even during the coldest winter days. That means there needs to be a way for the water to escape and flow away. If the land under the outdoor unit has shifted or settled, this may not be possible and you may need to have your outdoor unit re-mounted. A professional can help you check if this is what’s causing the issue.

If your heater freezes over and breaks down this winter, contact Jerry Kelly Heating & Air Conditioning today at 636.757.8506 and schedule a service appointment with our skilled and experienced team!