It’s hot outside, and your AC is working hard to keep you cool. But suddenly, you notice that the air isn’t as cold as it used to be, and then you realize…the AC unit is frozen!
Don’t worry, you’re not the only one this has happened to. In fact, it’s a common problem during the summer months.
This blog post will teach you how to troubleshoot and fix an outdoor AC unit that is freezing up in the summer heat!
What to do if your outside AC unit is freezing up in summer
If you notice that your outside AC unit is starting to freeze up, there are a few things you can do to troubleshoot and fix the issue. First, check the air filter and make sure it’s clean. A dirty air filter can restrict airflow and cause the AC unit to freeze. Second, check the thermostat and make sure it’s set to “cool” mode. If it’s not, turn it to cool mode and see if that fixes the problem.
Lastly, if the AC unit is still freezing up, you may need to call a professional for help. Call Weatherwise Heating & Cooling in Crystal Lake, IL today and we’ll be happy to help!
Causes of an outdoor AC unit freezing up in the summer heat
There are a few different reasons why an outdoor AC unit may freeze up in the summer:
One common cause is a dirty air filter. As we mentioned, a dirty air filter can restrict airflow and cause the AC unit to freeze. Generally, most air filter manufacturers and HVAC companies recommend changing your air filter every 90 days, or 3 months.
Another common cause is the thermostat not being set to “cool” mode. If your thermostat is set to “heat” mode, the AC unit will not turn on.
Another cause of an outdoor AC unit freezing up is low refrigerant. Refrigerant is what helps the AC unit cool the air, so if there’s not enough of it, the AC unit will freeze.
Low airflow is another common cause of an outdoor AC unit freezing up. If there’s not enough airflow, the AC unit will freeze.
Lastly, high temperatures can cause an AC unit to freeze. If it’s unusually hot outside, the AC unit may have a hard time keeping up and may freeze as a result.
Sometimes, an outdoor AC unit may freeze up due to a mechanical malfunction. It’s best to call a professional for help. Call Weatherwise Heating & Cooling in Crystal Lake, IL today so we can quickly assess the problem and get your AC unit up and running again!

How to prevent your outdoor AC unit from freezing up during the hot summer months
There are a few things you can do to prevent your outdoor AC unit from freezing up:
- Check the air filter regularly and replace it when it’s dirty.
- Make sure the thermostat is set to “cool” mode.
- If you have low refrigerant, have it refilled by a professional.
- If you have an older model AC unit, upgrade to a newer, more energy-efficient unit.
- Clean the coils on the outdoor unit regularly.
- If you live in an area with high humidity, use a dehumidifier to keep the air around your AC unit dry.
- If you have any trees or bushes near your outdoor unit, trim them back to allow for proper airflow.
- If you suspect your AC unit is frozen, turn it off and call a professional for help.
Quick tips for fixing an outdoor AC unit that is frozen solid
If your outdoor AC unit is frozen and you can’t turn it off, here are a few quick tips to help thaw it out:
- Inspect coils and fins: Check the coils and fins on the outdoor unit for ice build-up. If they’re covered in ice, use a hairdryer to thaw them out.
- Examine the air filter: A dirty air filter can restrict airflow and cause the AC unit to freeze. Replace the air filter if it’s dirty.
- Check coolant levels: If the AC unit is low on coolant, it will freeze. Add more coolant to the unit if needed.
- Turn off the AC unit: Once you’ve thawed out the coils and fins, turn off the AC unit. Let it thaw for a few hours before turning it back on.
- Reset the power: If the AC unit won’t turn on, reset the power by flipping the switch at the breaker box.
- Call a professional: If the AC unit is still frozen, call a professional for help. Weatherwise Heating & Cooling in Crystal Lake, IL is here to help!
Professional help for repairing or replacing a frozen outside AC unit in Crystal Lake, IL, and surrounding areas
When your outdoor AC unit is frozen, it can be difficult to fix on your own. That’s where a professional comes in. A professional can quickly assess the problem and fix it, so you can get back to enjoying the summer weather.
Not only can a professional help fix an outdoor AC unit that is frozen, but they can also help with other AC problems you may be having. If you’re noticing that your AC unit isn’t cooling the air as well as it used to, or if it’s making strange noises, a professional can help diagnose the problem and find a solution.
If your outdoor AC unit is old and needs to be replaced, a professional can help with that too. They can recommend an AC unit that is best suited for your home and lifestyle, and they can install it for you so you don’t have to worry about a thing.
If you’re experiencing problems with your outdoor AC unit, or if you just want to upgrade to a newer model, call Weatherwise Heating & Cooling in Crystal Lake, IL today. We recommend annual AC Tune-up services or take advantage of our Maintenance Service Plans. We serve McHenry, Lake, Kane, and Cook County, IL. When you choose Weatherwise you know you will get the best HVAC services in Crystal Lake, IL, and beyond.
More about us:
- Family Owned & Locally Operated
- 100% Satisfaction Guarantee
- Service All HVAC Makes & Models
- Free Estimates, Upfront Pricing
- 24/Hour Emergency Service
- Flexible Financing Options
We hope this article helped you troubleshoot and fix your frozen outdoor AC unit. If you have any further questions or need professional assistance, don’t hesitate to call Weatherwise Heating & Cooling in Crystal Lake, IL at 815-477-7766.