May 7, 2021
Frozen Air Conditioner in Northern California

It may seem a bit odd that your air conditioner freezes up. After all, they work on the hottest days of the year. This doesn’t stop the freezing issue. So long as the root cause of freezing isn’t addressed, you will still have problems. As long as the AC unit is running, it can create ice. While this may seem like a good thing, a frozen air conditioner will not cool your home.

How Air Conditioners Work

The first factor to understanding why an AC freezes up is knowing how it should be working. Air conditioners work by removing heat and humidity from your air and transferring it outside. This is accomplished by using a refrigerant. A compressor located outside will raise the pressure and temperature of the refrigerant to make it a gas.

This gas is sent to the condenser, cooled to a liquid state, and pushed into your home. The refrigerant then moves to the coil, where it evaporates and cools it. A fan forces hot indoor air over this coil, cooling the air and heating the refrigerant. This cooled air is circulated into your house while the refrigerant heads back to the compressor. The heat escapes into the outdoor air, and the refrigerant keeps circulating until your home reaches the desired temperature.

Your air conditioner works with a delicate balance. The refrigerant needs to be at the right level so that the pressure is at the correct level. You need good airflow so that the refrigerant heats up at the right time to properly cool the air. You also need a working blower to keep the air moving through the system. If any of these parts are out of balance, you’ll notice less cooling. The system will be knocked out of balance, and you’ll see all the parts working harder. This will cause wear and tear and drive up your energy bills.

Why Air Conditioners Freeze

Air conditioners freeze when the airflow over the evaporator coils is insufficient. This can be caused by components like a dirty filter or condenser coil. You may also see a frozen unit if there’s a refrigerant leak. High humidity will make the problem worse by adding extra moisture that can freeze. Many factors can lead to a lack of airflow to your condenser coils. This includes a blocked duct or clogged air filter. There may also be a problem with the fan, like low voltage, or it could be a bad blower motor. Dust can also block access to the coils. If there isn’t enough exposed surface area, your coil won’t get the hot air it needs to prevent a freeze.

Low refrigerant levels are another major cause. If you don’t have enough refrigerant, the compressor can’t maintain the proper level of pressure in the system. This is because the coolant heats up too quickly and drops the pressure in the unit. Remember, your air conditioner works because of a delicate balance. If it’s off, you’ll have problems like freezing. Your air conditioner also works best between certain temperatures. On cooler nights, you can end up with frozen coils.

Why Is Freezing Bad?

You may feel like a frozen air conditioner is a good thing. It seems like it would make it colder in your home. However, this isn’t the case. In fact, running your AC unit once it has frozen can cause damage to your compressor. Your air conditioner requires hot air to access the evaporator coils in order to cool your house. When that’s blocked, you won’t get cold air. Your system will try to work harder to cool the air, putting further pressure on the equipment. It will also use up more electricity. If you notice that your system is frozen, you need to take steps to fix the problem.

How to Fix Frozen Coils

If you check your outdoor unit and notice ice, you need to take some steps to correct this issue. You’ll need to cut power to your air conditioner and allow it to thaw out. This is best done if you’ll be out of the house. It may take up to a day, so be prepared to be hot. Once the coolant isn’t running through the coils, the hot air should help melt the ice. If you can’t turn off the unit fully, make sure only the blower is running. Don’t try to break off the ice since you might damage a component. You should never use sharp tools to chip away the ice.

Once the ice has melted, let the blower or fan run to dry the coils. Once the coils are dry, your system should operate normally. Just make sure you’ve taken the necessary steps to prevent future freezing, or you’ll be repeating this again. Regular maintenance on your part can save you a headache on a hot day.

How to Prevent Freezing

The best way to prevent future freezing depends on why your system is freezing in the first place. Cleaning off the coils will help. You should also replace the filter, and make sure the ducts aren’t clogged or collapsed. Inspect the fan and blower to ensure they’re operating properly. If they aren’t, you’ll need an HVAC technician to come out and repair it. Never run your AC unit if the blower isn’t working or if it’s frozen since this can cause expensive damage to your system. Compressors and similar parts aren’t cheap to replace.

You should also watch out for the weather. Cool nights and high humidity increase the risk of freezing. If the night is going to be cool, just open the windows instead of running the air conditioner. If you know the humidity will be high, keep a close eye on your system. So long as you keep up on other factors, you shouldn’t have as much of an issue. Humidity mainly makes other problems in the system worse. If humidity seems to be the main cause of freezing, you may need to talk to a local technician about what would fix the problem.

Regular air conditioner maintenance is important for keeping your unit running well. An experienced HVAC technician can make sure you don’t have any refrigerant leaks or low pressure that can cause freezing. They can also ensure all the parts of your system like your fan, blower, and ducts are working well. Regular maintenance is the best way to catch small issues before they become expensive headaches.

Your Solution to AC Problems

If you’re experiencing frequent AC freezes, our technicians at Gallagher's Plumbing, Heating and Air Conditioning can help. We’ve been serving the Sacramento, Los Molinos, and Northern California areas since 1989. We offer AC services like repair and maintenance to help keep your unit working well. We also offer AC installation if you need a new system. Our team can take care of heating, plumbing, ductwork, and more. You can get many of your home’s needs serviced with just one call to us. We’re fully licensed and bonded, and our company has an A+ rating with the BBB. Contact us today to make sure you don’t deal with a frozen AC unit ever again.

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