It may seem unlikely that a residential air conditioning system can freeze up, especially considering the high summer temperatures, but this is a common problem in Denver and surrounding areas of Colorado. A frozen AC unit causes a range of problems, so before you start looking for a new appliance, contact the experts at Summit Heating & AC. We will schedule a time for one of our technicians to come by and evaluate your cooling system. If the AC unit is frozen, we can perform the necessary repairs.

How Does an Air Conditioner Freeze Up?

Condensation is the root cause of all frozen air conditioners, but there are other contributing factors. Through normal operation, your AC unit creates condensation, but it typically drips into a drain pan. Airflow is another factor that causes the condensation to freeze. If there is not enough air moving around the coil, it does not have time to warm up, and the refrigerant freezes the condensation. Airflow problems may be caused by closed vents or dirty filters. In some cases, AC systems freeze up due to damaged fans, broken thermostats, and low refrigerant levels.

Outdoor Temperatures and Frozen AC Units

Although rare, we can have some fairly cool summer days in the Denver area. If the outdoor temperature is 62 degrees or lower, you should avoid running your air conditioner. You can turn it off or run it in fan mode only. Running the AC unit when it is cooler outside increases the likelihood of frozen coils. Cool air does not evaporate condensation as well as warm air, and water tends to collect on the coils much faster.

What Are the Signs of a Frozen AC?

Freezing around the coils of your air conditioner can cause several different symptoms, but they are not always obvious. The AC unit will continue to run if it is frozen, but it will not cool the air. In many cases, the indoor temperature will actually increase. Another sign of a frozen air conditioner is reduced airflow in your Denver home. The air may feel stuffy, or you may notice that less air seems to be coming out of the vents.

Why Does the AC Keep Running if It Is Frozen?

Condensation is a normal part of the AC cooling process, and the water typically drains away from the equipment. When the coils freeze, the drain hole gets clogged. The air conditioner continues to run because all the mechanical parts are still working. The system continues to circulate air as normal, but the malfunction of the coils combined with warm outdoor temperatures results in warm air instead of cool air blowing from the appliance. Because the system keeps running with frozen coils, you are using more electricity but not feeling comfortable and cool.

How to Check for Frozen Coils

You can check for frozen coils on your own if you would like, or we can send a technician over to your house. You should shut off the AC unit right away. Running an air conditioner with frozen coils damages the compressor. Open the service panel on the AC unit, and then check the coils. You may need a flashlight to see the components. You are looking for the copper coils, and any ice will look like frost.

Troubleshooting a Frozen AC System

If you determine that your AC unit is frozen, you should not run it until the ice has melted from the coils. In the meantime, you can do a few things to prevent the problem. First, check to make sure that all the vents in your home are open. This includes the intake vents. Be sure to leave at least two feet open in front of the intake vents. Next, change out your filter, even if it looks clean. Lastly, check the drain near the coils, and be sure to remove any ice or debris. Also, empty out the drain pan and clean it. Once the ice is melted, you can try to run the AC unit again to see if ice builds up on the coils. If it does, it is time to call a professional from Summit Heating & AC.

When to Call a Professional AC Technician

If you open the vents and replace the filter but still have ice on your coils, we recommend that you have one of our technicians take care of the problem. We will check the thermostat and refrigerant levels as well as any other possible causes. We will also inspect the compressor, fan, and other components for any signs of damage.

Frozen AC Units and Your Ducts

Often, we find condensation inside the ducts after an air conditioning system has frozen during the summer. You may be tempted to leave the water to evaporate, but we do recommend that it be removed. Water combines with any dust in the ducts to create a sludge that dries and interferes with airflow. Moist environments are also ideal places for mold and mildew to thrive, and little pests love to make nests near a source of water. Cleaning your ducts takes very little time, and we will also inspect for any damage that may increase your energy consumption.

How to Prevent a Frozen AC System

Summit Heating & AC offers routine maintenance for cooling systems. We recommend the maintenance in the spring, and the steps we take can prevent freezing around your coils. There are also some things that you can do to prevent a frozen air conditioner this summer.

  • Change your filters every month, even if they look clean.
  • Check your drain and drain pan each week.
  • Keep the refrigerant at the proper level and look for any leaks.
  • Keep all outflow and intake vents open.
  • Perform repairs when needed.

Consider a Zoning System

If you determine that your coils are freezing because of closed vents in your home, you may want to consider a zone system. This type of system achieves the same goals as closing vents: to focus cooling on occupied areas of the home. A zoning system comprises louvers that are installed inside the ducts and thermostats that are mounted within each zone of your house. When only one part of your home needs cooling, the louvers adjust to only allow air where it is needed. The system is designed to work with your cooling equipment without causing the problems that occur when you close the vents.

Need a New AC?

If it is time to replace your air conditioning system, be sure to speak with the experts at Summit Heating & AC. We will help you find the right-sized unit for your home, and we can also recommend some upgrades, such as a programmable thermostat or an air purifier.

If you have questions about a frozen AC unit or other HVAC issues, we are happy to help! Call Summit Heating & AC today, and one of our professional staff members will give you the answers you need. We offer installation, repair, and maintenance services for residential heating and cooling systems. Be sure to ask about our indoor air quality products as well.

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