Cold, Hard Facts – 5 Causes of Frozen Air Conditioning Coils

Air Conditioning Replacement ServiceWhen a heatwave hits here in Southern California, air conditioning isn’t a luxury – it’s virtually a necessity. So it can be extremely frustrating – and quite concerning – when the AC begins to struggle or shuts down completely.

One of the most common problems we see with customers’ air conditioners is frozen coils. In this article, you’ll learn the top five causes of frozen coils and what to do if the situation happens to you. 

Why do AC coils freeze?

There are a number of reasons why air conditioning coils would freeze. It’s important to identify the right cause in order to fix the issue so it doesn’t happen again.

  1. Broken thermostat – The issue may not be with the AC unit but rather the thermostat. First, make sure the set temperature is correct (you wouldn’t believe how many times the thermostat gets bumped or changed by kids). Next, check that the air conditioning is turning off when it hits the desired temperature. A faulty thermostat can cause the AC to run continuously, increasing the risk of frozen coils.
  2. Dirty air filter – If the filter is clogged with dust, pet dander, and other small particles, the airflow is restricted. Without proper air circulation, the coils get colder and colder until a layer of ice forms.
  3. Low refrigerant – More times than not, low refrigerant levels are caused by a leak in the coils or refrigerant line. Not only will this limit the AC’s ability to cool your home but it can put extra wear and tear on the unit, meaning it may break down sooner. An HVAC professional will be able to find the leak, fix it, and add the proper amount of refrigerant.
  4. Issue with the fan – While you’re checking the air filter, take a look at the blower fan. If the blades appear dirty, it may be affecting the airflow as well. It’s also possible that the fan motor is broken and need to be replaced.
  5. Blocked condensate lines – As the AC draws out humidity from the inside air, the moisture is condensed into water and drained outside or into a drain. But over time, this condensate pipe can get clogged by algae growth or debris. If water gets backed up into the unit, it can cause the coils to freeze.

What to do if your AC coils freeze

When you notice that your air conditioning isn’t working properly or ice forming on the unit, turn it off immediately to prevent further damage. You can let the ice melt but this most likely won’t fix the underlying issue. If some of the easier solutions – adjusting the thermostat and replacing the air filter – don’t resolve the issue, then it’s time to bring in an air conditioning professional.

Just because your AC coils are frosty doesn’t mean you have to suffer in stifling heat. Call Liberty Plumbing at (951) 760-4215 and one of our technicians will come over and fix the problem right away.