What To Do When Your AC Unit Freezes Up?

It’s not just Jack Frost who freezes your AC unit. Many people using air conditioners to cool down in the hot summers end up with frozen air conditioners. 

It happens pretty frequently, and what’s worse, running a frozen air conditioner can break the compressor. You end up with expensive repairs if ignored. Instead, it’s better to try and unfreeze the air conditioner. Here are 6 answers to your question: What to do when your AC unit freezes up? 

what to do when your AC unit freezes up

How Do You Unfreeze An Air Conditioner? 

There are numerous ways to try and unfreeze an air conditioner. However, never try breaking up the ice using something heavy or sharp. It can damage the AC components and create more problems. 

Instead, you can try to unfreeze the unit by:

1. Thawing It Out

First, try thawing out the air conditioning by turning off the thermostat. Then turn on the fan and leave it on for a few hours to let the unit defrost. Once the AC is defrosted, turn on the air conditionings thermostat to once ‘cool’ the unit. You know the air conditioning is okay when the air coming out is cooler than the room’s temperature. 

2. Cleaning The Filter

A clogged air filter can stop the unit’s working. All it takes is a thin layer of dirt on the filters to prevent warm air from flowing through the AC. Warm air is essential to prevent the unit from freezing up. 

You can clean the filter by placing it underwater. Then wait till it is dry before putting it back. You can alternatively buy a new one, depending on the type of filter your air conditioner has.

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3. Checking The Condensate Drain

A clogged drain may lead to a condensate pan not draining correctly. Sometimes the water dripping into the pan may contain dirt. The dirt, with time, clogs the drain and leads to an eventual overflow. 

Overflows are dangerous. They lead to water damage while the excess water around the unit freezes. Removing the clog in the drain can help solve the problem. 

4. Check The Coils And Fins

Another thing you can do to fix a frozen air conditioner is to see if the coils and cooling fins surrounding the evaporator need cleaning. If they do, use a soft brush to remove the debris and dust gently. 

5. Check Supply Registers

Also, check if the supply registers to all the rooms are open because blocked registers also restrict airflow. The blocked airflow can, in turn, affect the evaporator temperature and lead to problems. 

6. Check Coolant Levels

Do check the coolant levels because low levels can affect the unit’s pressure and cooling efficiency. 

It is generally better to have a professional check your air conditioner’s coolant levels. However, you can also try using a coolant installation kit to check and correct your air conditioner’s refrigerant levels. 

How Long Does It Take To Thaw A Frozen Air Conditioner?

A frozen air conditioner usually thaws out in an hour. However, you may need to leave the fan on for 24 hours in extreme cases.

What Causes The Air Conditioner Unit To Freeze Up?

There are various reasons for a frozen AC:  

  • Air conditioners require flowing air all the time to keep their cold coils warm. The surrounding warm air helps in this process. It keeps the coils cold and maintains the units’ above freezing temperature. 

Without adequate airflow, the air conditioning coils will end up frozen even before the condensed water can drain away. 

  • Dirty air filters and closed air registers can block the airflow. So check that both are clear and open. 
  • Low refrigerant levels lead to too cold coils while a faulty fan prevents air movement. 
  • Clogged drainage holes are another common reason for an air conditioner to freeze up. The air conditioner’s cooling process involves condensing the water vapor into liquid and draining it outside. 

Sometimes debris and twigs can block the drainpipe, so check and remove these blockages. While the air conditioner may run with a blocked drainpipe, it will not do a good job cooling your home. Besides, it will end up consuming much more electricity. 

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Can I Pour Hot Water On a Frozen Air Conditioner?

Yes, you can. Pouring hot water helps melt the ice and thaw the air conditioner faster. The water doesn’t even have to be extremely hot. Even warm or running water will work. 

Just make sure you disconnect the AC from the primary power source before pouring water. And pour water only on the coils. Do not splash or throw water and ensure the water drains outside. 

You must be careful because the air conditioner is an electrical device. Pouring water recklessly can lead to a short circuit or an electrical fire.  

Can A Dirty Filter Cause AC To Freeze?

Yes, a dirty filter can cause an AC to freeze because it limits airflow. Lack of airflow around the unit increases humidity levels and precipitation on the coils. Even too restrictive air filters can make the AC freeze up. 

Can I Use A Hairdryer To Defrost My AC?

Yes, a hairdryer will accelerate the melting ice process. But run it only on the lowest setting possible as high heat can damage the AC unit. 

Can You Spray The Outside AC Unit With Water?

Yes, you can spray outside AC units with water to keep them clean and to help them run more efficiently. 

Hopefully, you’ve found the answers to your question on what to do when your AC unit freezes up? Don’t worry when it happens. It can happen to anyone, even to the most careful homeowners. The critical thing to do is to defrost it as soon as possible.

And while defrosting the unit helps, it only provides temporary relief. It’s best to prevent your AC from freezing by applying all the tips mentioned above on a regular basis.

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