Are you wondering how to fix a frozen AC unit? If so, we can help.
In this guide, you will learn:
- What causes your AC to freeze?
- What should you do if your AC freezes?
- Is it safe to use a frozen air conditioner?
- How can you prevent your AC from freezing?
AC units freeze over for a number of reasons. However, if your air conditioner is freezing it is definitely a sign that your system is not running properly.
So, here is everything you need to know to get your HVAC system running properly.
What's In This Guide?
What Are The Most Common Reasons For Your AC Unit To Freeze Up?
There are a number of things that could make your AC unit freeze. Your HVAC system needs a steady supply of warm air and coolant to properly condition the air. When those elements are not balanced, your indoor or outdoor unit can freeze.
Some of the most common reasons your air conditioner may freeze over are:
- Damaged return vents
- Low refrigerant levels
- Dirty air filters
- A broken air compressor
- A dirty evaporator coil
While these are some of the most likely causes of your HVAC freezing, there are many reasons your AC can ice over. Some causes are more easily identifiable than others.
What Should You Do If Your HVAC Freezes?
If your HVAC is freezing, you should turn it off to allow it to thaw before troubleshooting. If the system is freezing it will not run efficiently, and probably won’t cool your home well anyway.
While your system is thawing, you should perform a few DIY maintenance tasks to be sure your system is running efficiently. If your system is low on refrigerant a clogged evaporator coil can make it worse.
Plus, it can help your HVAC repair professional identify and correct the issue if you can give them some information about the condition of your air conditioning system.
Check For Signs Of Low Refrigerant Levels
AC freezing often means your HVAC refrigerant levels are too low. If this is the case, it can cause your AC to freeze very quickly.
You will want to check for ice on the refrigerant lines as soon as you turn your air conditioner off. If your refrigerant levels are low, you will likely find ice on the refrigerant lines.
The refrigerant lines lead from the base of your outdoor unit to your home. You may also find that your evaporator coil and even the condenser unit outside are frozen over.
If you see ice on the lines, it is important to keep your air conditioning system off until an HVAC system can look at it. Continuing to run your system with low refrigerant levels can damage indoor and outdoor air conditioning units.
Only a licensed HVAC technician can lawfully handle refrigerant. Plus, your HVAC professional will check for refrigerant leaks and complete any necessary AC repairs before recharging your system.
Change Your Air Filters
Clogged or dirty air filters can restrict airflow and cause your unit to freeze. The average homeowner should change their air filters at least once every 30 to 60 days.
In homes with more people or pets, you should change the filters more often. If your indoor AC unit is freezing, you may see ice on the air filter.
If the filter is frozen to the evaporator coil, you will need to wait until the ice melts to remove it. Before replacing the filter, check the evaporator coil.
Care For Frozen Evaporator Coils
Dirty evaporator coils can prevent your system from cooling efficiently and may cause ice build-up. If you see ice on the evaporator coil, you need to wait for it to melt.
Trying to clean your evaporator coil while it is frozen or pouring warm water on it to melt the ice could damage it. Once it is safe to do so, follow these instructions to clean the coil:
- Turn your AC unit off.
- Turn power to the unit off at the circuit breaker.
- Make sure the condensate drain is clear.
- Brush and debris off with a soft bristle brush.
- Coat the evaporator coil with a cleaning solution.
- Let the coil cleaner soak per the instructions on the container.
- Use a water hose to remove the cleaner and buildup.
- Let the coil dry before turning your air conditioner back on.
Turn Your Air Conditioner Back On
If your refrigerant lines were not frozen, you can try restarting your air conditioner once you clean the evaporator coil and change your air filters. However, you will want to keep an eye out for any ice.
You should also check to make sure that there is cool air coming out of your air vents. If your thermostat is set correctly and your air conditioner is not properly cooling your home, you should have someone look over your system.
What If Your Air Conditioner Is Still Freezing?
If your air conditioner is still freezing, it is likely a sign that something more serious is wrong. If you have not had an HVAC tuneup recently, the best thing you can do is schedule an appointment with a repair professional.
They will go over your entire system with a fine-tooth comb making sure the blower motor, blower fan, ductwork, condenser, and evaporator are working. If your system needs a tuneup, it will perform any necessary maintenance.
What Is The Best Way To Keep Your AC From Freezing?
The best way to prevent freezing in the first place is to take care of your air conditioner. Performing routine maintenance like cleaning your evaporator coil and changing your air filters can extend the life of your HVAC system and prevent your system from freezing over.
It is also a good idea to have semi-annual tune-ups. Your HVAC professional will cover your entire system, top off the refrigerant, and check for any parts that they need to replace. So, you do not have to worry about ice buildup on your air conditioner.
For more information on why your AC may be freezing, check out this video:
Final Advice When Your Air Conditioner Freezes
When ice forms on your air conditioner, it is a sign that your unit is not running efficiently. The best way to prevent your AC from freezing is to prevent your system from running inefficiently in the first place.
Aside from performing routine maintenance like changing your air filters, a home warranty is the perfect way to keep your AC system working well year-round.
With a home warranty that covers your HVAC system, if you notice ice build-up on your central air conditioner, all you have to do is contact your provider. They will schedule a service call with a knowledgeable HVAC professional so they can diagnose the problem.
If your plan covers the repair, all you have to do is pay the deductible and your home warranty provider will cover the rest up to the limit on your policy.