Why Air Conditioner Coils Freeze UpHave you noticed that your air conditioner isn’t blowing cold air? If you’ve already checked your thermostat settings, as well as replaced your air filters, there’s a good chance there’s another problem at hand. 

When you take a look inside your outdoor condenser unit, you may have found that your evaporator coils are frozen, and now, you may be asking, “Why did my air conditioner coils freeze up?” 

In this article, we’ll be discussing just what your evaporator coils do, a few of the reasons why air conditioner coils freeze up, and what your next step should be. With this information, we hope you’ll be able to solve your AC troubles ASAP!

How Do Your Evaporator Coils Work?

Before diagnosing the issue, it’s important to understand how your evaporator coils work. Your air conditioner does its job using refrigerant. The refrigerant pulls the heat from the air inside your home, and your evaporator coils play a vital role in doing so. 

Your evaporator coils help to cool down the refrigerant, so that the refrigerant can absorb the heat from the air in your home. First, the refrigerant passes through the evaporator coils, and as it does so, the fan blows air on the coils, which helps to cool the refrigerant and turn it into a gas. Once in this state, the refrigerant can absorb heat and continue the cycle of your AC cooling your home.

During this process, your evaporator coils should be cool, or around 40 degrees. When your evaporator coils freeze, and prevent the proper flow of the refrigerant, your AC unit won’t be able to do its job. Oftentimes, you can spot frozen evaporator coils with your own eyes, as the frozen condensate will appear like crystals on your evaporator coils and your refrigerant lines.

What Causes Them to Freeze?

While there are many reasons your evaporator coils may be frozen, there are two primary causes that may be to blame. Let’s take a moment to look a bit further into them.

1. Your system is experiencing restricted airflow.

The first reason why your evaporator coils may be frozen is your air conditioner is experiencing restricted airflow. The problem with restricted airflow is that it causes your system to overwork, thereby causing your unit to cool the refrigerant more than necessary and freeze your evaporator coils. 

Clogged air filters can cause restricted airflow. Thankfully, you can replace your air filters yourself. However, if the issue is more significant, such as damaged ductwork or a broken blower motor, you will most likely need the help of an HVAC professional to identify and repair the issue. 

2. Your system is low on refrigerant.

When restricted airflow isn’t the issue, there’s a strong chance that low refrigerant levels are the cause of your AC troubles. Much like how restricted airflow can cause your air conditioner to overwork itself, your system can also overwork itself when low on refrigerant. In addition to this, the lack of pressure from the missing refrigerant can cause your evaporator coils to become even cooler than they should be. 

Unfortunately, when your system is low on refrigerant, it’s often indicative of a refrigerant leak. For more tips on how to identify a such a leak, consider reading our article: AC Refrigerant Leak Signs You Should Know. With that said, if your system has a refrigerant leak, you’ll most likely need to replace your entire HVAC system.

What Should You Do Next?

We’ve discussed just some of the reasons why your air conditioner coils could be freezing up. Once you have identified the cause of the issue, it’s time to be proactive and get your system fixed! Most likely, you’ll want to get in touch with an HVAC professional who has the knowledge and skills to solve your AC troubles as soon as possible.

At Edge Heating & Air, our team has been repairing and upgrading heating and air conditioning systems for over 15 years. With our 24/7 emergency services, we can send an HVAC technician straight to your door to find out exactly why your air conditioner coils are freezing up.  

To repair your AC, call (951) 304-9658 or schedule your service online.