How Do I Keep My Air Conditioner From Freezing Up? 4 Effective Tips

Josh Miller

Josh is a contributing writer to the site and former HVAC specialist.

Last Updated on November 24, 2021

Air conditioners are versatile and highly functional units that replace the hot, humid, and muggy air in your living space with cool, clean and fresh air. They also often have integrated air cleaning filters that extract harmful solid particles like smoke, dust, dander, and pollen from your house. This filtration process can help alleviate your allergies and allow you to breathe easier.

However, if you fail to look after your AC unit correctly, you’ll find that parts of the system freeze up, causing the machine to emit air that’s neither cool nor clean, causing you to waste electricity running the unit for no reason.

air conditioner at the living room
Share on facebook
Share on twitter
Share on pinterest
Table of Contents

What are the Main Causes of Your Air Conditioner Freezing Up?

Before answering the question “how do I keep my air conditioner from freezing up? it’s crucial to consider what causes the unit to freeze. There could be several reasons why your air conditioner system has frozen up, from lower than normal refrigerant levels to a congested air filter preventing hot air from reaching the unit’s evaporator coil. Once you can determine the root of the problem, you can find ways to solve the issue quickly and effectively.

window electronics

Here are a few of the significant factors that cause your air conditioner to freeze up:

  • Issues with the fan’s speed

If the conditioner system’s built-in fan is moving too slowly, then the hot or humid air doesn’t flow quickly enough across the evaporator coil. As this airflow decreases, the evaporator coils cool, eventually freezing up. When this happens, the ice inside the coils clogs up the drain hole, leading to the entire unit malfunctioning.

A completely blocked off drainage hole could also cause a flood when the water inside the unit’s drain pan leaks and bubbles over, hitting the integrated blower motor and soaking the surrounding floor of your living room or bedroom.

  • Problems with the conditioner’s drainage system

Your air conditioning unit may be experiencing issues with its drainage system, which can cause the evaporator coils to freeze up. When hot air flows across these pipes, the cold coil extracts the heat. This heat becomes warm liquid in the condenser section of the unit.

The collected heat then drains out into your backyard or the drain pan at the base of the unit. If there’s a problem with the drainage system, this initially hot water sits stagnant in the pipes until it eventually cools and freezes up.

  • Issues with the refrigerant levels

One of the most common causes for air conditioners freezing up is that of low refrigerant levels. The refrigerant is the substance that flows through your air conditioner’s coils in a low-pressure gaseous state. When hot air passes over these coils, the refrigerant absorbs the heat from this air and turns it into a liquid. It then cools and turns back into a low-pressure gas.

If there’s a leak in your air conditioning system and your refrigerant levels are lower than expected, this causes the refrigerant pressure to drop inside the evaporator coils. The heat levels inside the pipes then decrease as a result of the pressure drop, leading to the coils freezing up.

  • Problems with the filter

Another common source of air conditioners freezing up is using a poor-quality filter. If your unit’s filter is poorly designed or unclean, it will likely become clogged up with dust, dander, and other bits of dirt that block the initial airflow into the conditioning system.

When this airflow decreases, there’s less warm air moving across the cold evaporator coil, causing the pipes to freeze in certain places. Once some sections of the coil freeze up, the unit’s integrated compressor pump will become damaged. This type of damage could mean you have to replace the entire AC system.

How Do You Keep Your Air Conditioner From Freezing Up?

Once you know the main causes of freezing up, you can learn the answer to, “how do I keep my air conditioner from freezing up?  While having tools to help you develop an effective solution once your air conditioner freezes is helpful, you can also use this knowledge to avoid the problem of your unit freezing up in the first place.

Follow these steps to avoid the most common problems and to keep your air conditioner from freezing up:

1. Avoid or fix low refrigerant levels

If you think that there’s an issue with low refrigerant levels in your air conditioner unit, you should get a certified technician to check your system’s levels. These professionals can determine whether there’s a problem. If there is, they’ll seal up the leak and recharge your AC by refilling it with refrigerant.

2. Avoid or fix a drainage problem

If you think there’s something wrong with your unit’s drainage system, you should check the condensate drain at least once a week. If you notice this drain is clogged or dirty, clean it out.

Turn off the power to the AC unit, then suck up the stagnant water in the drain pan with a wet vacuum cleaner. Next, find the nearest access point on the drain line and remove the lid to clean the inside of the drain with equal parts water and vinegar solution. Leave the distilled liquid to rest for 30 to 60 minutes, then flush the drain with some water until you’re satisfied that it’s flowing through the condensate drain properly.

3. Avoid or fix slow fan speed

If you think that there might be an issue with the integrated fan’s speed, you should get an HVAC technician to come in and check this speed. If they think it’s moving too slowly, they’ll increase its rate manually or decrease its speed if it’s too fast.

4. Avoid or fix a congested filter

Those who are worried about a dirty filter should inspect the filter regularly. If your unit has an air cleaning filter, change it every few months. Doing this ensures there is always a steady stream of air moving over the evaporator coils. It also allows your AC unit to extract irritants and pollutants from the air before circulating fresher, cleaner air back into your room.

You’ll need to clean standard air filters every 2 to 3 weeks. Open up the unit’s front panel, then remove the filter with your hands. You can clean this component with a vacuum or by running it under some warm tap water.

Keep Your Air Conditioner From Freezing Up With These 4 Actionable Tips

Investing in an air conditioner is the ideal way to improve the air quality inside your home. These innovative units remove contaminants and allergens from the air in your living room or kitchen, releasing refreshingly clean and cool air back into your home.

However, if you don’t look after your AC unit correctly, you’ll find that the evaporator coils or drainage pipes freeze up, causing the system to stop working effectively. To avoid problems, monitor and clean your air conditioner regularly.

Related articles:


Affiliate Disclaimer is a participant in the Amazon Services LLC Affiliate Program, an affiliate program designed to provide a means for sites to earn advertising fees by advertising and linking to

Share on facebook
Share on twitter
Share on linkedin
Share on pinterest