How an AC Compressor Can Freeze

Ice is usually something you dread running out of. But only the cubed or crushed variety. Ice anywhere else usually spells trouble – one such trouble spot is when ice forms on your outdoor air conditioning unit.

How does that happen? Air conditioners need a steady flow of air to keep the internal coil warm. Without that air, coils freeze before the condensed water can be drained from the unit.

AC Compressor Can Freeze

So, if your AC compressor is caked with ice, start by checking the system’s indoor air filter and registers. If any are clogged, clearing them might solve the problem once the ice melts. You’ll first need to turn off the AC system to give the ice time to disappear. A frozen compressor also can be caused by low refrigerant levels or a faulty fan that prevents adequate airflow.

Outdoor condensing units also can freeze when operating in cooler temperatures. If that’s happened to your system before, consider having an ambient temperature sensor installed, designed for exactly these occasions.

Here are two other frequent causes of a frozen AC compressor:

  • Thermostat problems. The air conditioner may run all night even when it doesn’t need to. That wastes energy and money while possibly causing your air conditioner to freeze. Have the thermostat checked out to solve the issue.
  • Refrigerant Leak. Your system might be low on refrigerant. Either the refrigerant charge is off, or you’ve got a leak. Here’s what’s going on. You’ve set your thermostat to a comfortable temperature. 75 degrees, say. When you do this, you’re telling the system, “Make the refrigerant running through these coils expand enough to cool my home to 75 degrees.” That’s all fine and good when there’s enough refrigerant in the system. It’s not so great when you’re telling a smaller quantity of refrigerant to expand just as much as the normal amount would have to expand. Ultimately, the temperature of the coil itself hits the freezing point and ices over.

Not matter what the cause might be, shut off the power to your AC system as soon as you notice ice forming either on your outside compressor or indoor air handler. And then contact Optimum Air to fully resolve the problem.  As skilled and experienced AC service providers, we’ll diagnose the problem, explain to you what happened, and give you a guaranteed price quote to get your system back up and running. That’s the kind of service we’re known for.