Why Do Air Conditioners Freeze?

Why Do Air Conditioners Freeze?

Summer is just around the corner and that means that before long you’re going to be firing up your air conditioner to stay cool when California cranks up the summer heat. It also means your air conditioner can face the threat of a number of different issues, including the possible issue of your air conditioner freezing which can bring your air conditioner to a halt right when you need it the most. It may not make sense that something can freeze on a hot day, but it’s more likely than you think.

What Causes an Air Conditioner to Freeze?

An air conditioner can freeze when so much frost accumulates over your indoor air conditioner’s coil that it shuts down and has to defrost before it can continue to operate. Trying to run a frozen air conditioner can lead to broken components, extra strain on the most important parts and plenty of other problems, which is why most modern systems will automatically shut off if they detect they’ve frozen over.

There are many reasons why your air conditioner can freeze over and identifying exactly which one is causing the problem can be tricky unless you have the knowledge and experience from years of training. However, there are a few things you can generally check. Here are just a few of the most common causes of a frozen air conditioner:

  • Dirty air filter: this is usually the primary culprit of a frozen air conditioner. When your air filter is dirty, the airflow through it reduces to a minimal level. This low airflow means that your refrigerant in your coil can’t absorb enough heat to keep the cycle running smoothly and thus it freezes over.
  • Closed supply registers: shutting the supply vents in your home is not a good idea. These are the vents that draw air into your system for it to cool and distribute back through your home. They usually look exactly like a regular output vent, which is why some people accidentally close them. However, closing a supply vent can cause your coil to freeze and your system to shut down. It’s important to maintain the maximum airflow through your system at all times
  • Low refrigerant levels: your air conditioner can freeze when there is not enough refrigerant in the system. This is usually the result of a small leak in your system which needs to be repaired. Call us as soon as possible to have your system inspected and the leak found.
  • Drainage problems: your air conditioner removes humidity from the air and that means the condensed humidity (now in water form) needs to have somewhere to go. If your drain line is clogged, then the water can re-evaporate back into humidity that continues to build up and freeze on the coil, resulting in a frozen system.

How to Fix a Frozen System

The easiest way to fix a frozen air conditioner is to simply shut it off and let it thaw out. If possible, you may be able to take a heat gun and carefully assist the frost on your coil in melting down, but make sure you take every effort not to accidentally burn an important part of your system when doing this. If you find that your system freezes over regularly, then you more than likely have one of these or another underlying issues.

If your air conditioner has frozen over, get it repaired by calling Valley Heating, Cooling, Electrical and Solar at (408) 868-5500! Contact us today to request your service quote.

Elsewhere on the Blog

Elsewhere on our blog, we took a look at two other issues that frequently impact homes in California. If you have an older system, you may have been shocked to discover that the cost of your general maintenance or otherwise simple repair is so high. Why? Because R-22 refrigerant, also known as “Freon,” is now extraordinarily expensive. Our blog explored why this is the case and explained how actually replacing these old, outdated systems could be by far the more economically-viable option for getting it fixed.

We also took a look at some of the common electrical issues that homes face when it comes to electrical codes. Electrical codes are pretty complex, but they are designed for our safety—when a weakness in electrical systems is exposed, a solution is developed, and that solution becomes part of our series of codes. However, unless your home is brand new, there’s a good chance you more than likely have at least one common code violation in your home. This is normal—codes change and they put everyone who followed the old code out of date when they do. On our blog, we took a look at some of the most common code violations that we see and explained how to fix them.