What to Do If Your Home AC Freezes

A home air conditioning unit with ice build up, an AC freeze example.

You might not realize this, but air conditioners freeze up. This is actually a common issue for both business and home AC owners. And, you might think having your AC freeze up would mean it produces more cold air, but this simply isn’t true.

Your air conditioner’s main components work simultaneously to provide you with summer-long comfortable temperatures. These components include:

  • Condenser coil
  • Compressor
  • Expansion valve
  • Refrigerant
  • Evaporator coil

Your air conditioning unit works through a refined control of airflow, temperature, and pressure. If one or more of these fall out of balance, your refrigerant system that’s responsible for creating the cold air, could freeze up, without cooling the air more. If your air conditioner freezes up, it will either blow cool/warm air or won’t blow any air at all. 

Reasons Why Your AC Could Freeze Up

Some reasons why you might have a problem with your air conditioner freezing up are:

  • Airflow obstruction
  • Dirty air filter
  • Dirty evaporator coil
  • Refrigerant leak

When your AC struggles from poor airflow, its evaporator coil becomes too cold and freezes. This is because the evaporator coil in your AC is really a group of refrigerant coils. As the chemical refrigerant passes through, it reaches low 10 to 20 °F temperatures.

Now, unconditioned, warm air will pass over the coils during normal operation. Your household’s existing warm air prevents frost or ice formation. But, if your home lacks warm airflow across the evaporator coils, then they’ll ice over and the ice can travel along the refrigerant lines. 

If your air conditioner freezes, you’ll notice frost buildup on the copper coming out of your unit. In some cases, this build-up of frost could be so bad it causes a full block of ice. Fortunately, it’s fairly easy to solve this problem. 

Handling an Air Conditioning Unit that Freezes Up

Below are five things you can do if your home AC freezes up.

1. Assess the Vent Filters

You’ll want to take a peek at the vent filters to see if there’s an obstruction that restricts airflow. If your AC’s filters are dirty, it could lead to your system freezing up. If the filters look discolored or dirty, change them and check to see if this fixes the issue.

2. Check Coolant Levels

If the coolant levels are low, it could impact your air conditioner’s pressure and cooling efficiency. This can cause your AC to freeze up. You can purchase a coolant installation kit from your local home improvement store to check on your AC’s refrigerant levels, but if you suspect your system is leaking refrigerant, it’s important you contact a professional HVAC technician to come take a look and repair the leak if necessary.

3. Thaw it Out

Turn your air conditioner off at the breaker and allow it to thaw. Take note, it might take an entire day to totally thaw out the ice. So, you’ll want to choose a day when you know you’re not going to be home. You’ll want to consider your pets too as your home could get very warm with no AC running and this could get very uncomfortable for them. If you can’t get away from your home and you need to thaw the unit out, you can still keep the air conditioner off, but run the blower.

It’s important you don’t use your air conditioner when the coils are frozen. If you run your air conditioner with frozen evaporator coils, it can strain your AC’s compressor. This is the most costly component in your AC system. This strain can damage this costly part, setting you back with an unexpected expense.

Also, don’t be tempted to break the ice up with a sharp tool. This could easily cause damage to the components and create new issues.

4. Dry the Evaporator Coils

After the ice thaws, you’ll want to dry the coils. Restore the power of your AC unit and turn the blower on, setting the thermostat to only run the fan or blower. Doing this will circulate the air through and around the coils, drying them quickly. After the coils are dry, you should be able to run your system normally. 

5. Turn the AC Back On

After you allow your air conditioner to thaw for a reasonable amount of time, you can turn the thermostat back to “cool.” If you notice the air coming out of the system is cooler than the air in the room, you’re all set and your AC is running properly.

It’s always a good idea to call a professional HVAC technician and inform them of this issue, even if you fix it yourself, and have them come to your home to inspect your AC system. An AC freezing up, particularly if it occurs repeatedly, could be a sign of another issue.  The sooner you can catch bigger problems, the better it will be for your home and your wallet!

If you’re having problems with your AC freezing up, you suspect a different issue or you’re simply looking to set an appointment for routine maintenance, Larry’s Heating & Cooling has your back.

Get AC Repair in Yankton, SD

 Contact us today to schedule your appointment to ensure your air conditioning system is running properly to keep your home comfortable this summer. Our AC repair company serves those in Yankton, Vermillion, and the nearby communities.

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