During the heat of summer in Glen Carbon, your AC system is probably running nearly nonstop. Yet despite keeping windows shut and adjusting the thermostat, something feels off—your system is blowing warm air, or even worse, it’s forming ice. AC freezing might seem strange during a heatwave, but it’s a more common issue than many homeowners realize. The problem can sneak up silently and compromise your home comfort when you need cooling the most.
When the AC freezes, it’s usually not the outside temperature that caused it. The issue often starts inside the system due to airflow blockages or refrigerant problems that prevent the unit from working like it should. Addressing the problem early keeps your cooling system under less strain and helps avoid long-term damage. Understanding what leads to a frozen AC is the first step to solving the issue and keeping your home in Glen Carbon cool and comfortable.
Common Causes Of AC Freezing Up
When your AC suddenly starts forming ice, there’s a deeper issue at play. Even in high temperatures, the inner components of an AC system can freeze up under specific conditions. Below are some of the most common causes:
1. Insufficient Airflow
Air needs to move freely through your system for the evaporator coils to function correctly. If there’s a clog or blockage that reduces the airflow, the coils may get too cold and freeze. Some reasons for limited airflow include:
– Dirty or clogged air filters, which trap dust and debris and restrict circulation
– Closed or blocked return vents that stop air from entering the system
– Obstructed or crushed ducts that slow down air movement
When airflow slows down, the evaporator coil doesn’t get enough heat from your home’s air, which can cause moisture on the coil to freeze.
2. Low Refrigerant Levels
Your AC needs the right amount of refrigerant to absorb and carry heat out of your home. When levels drop—usually from a leak—the pressure inside the coil drops as well, causing it to absorb less heat and freeze up. A frozen coil can quickly lead to damage if the compressor becomes overworked or overheated due to the blockage.
3. Thermostat Problems
A thermostat that isn’t reading the room temperature accurately or is set too low for long periods can keep the system running nonstop. When the AC runs too much without cycling off, the evaporator coil stays cold and may freeze over. If your AC never seems to shut off, the thermostat might be part of the issue.
4. Mechanical Failures
Key components like the fan motor or blower can break or wear down over time. If they aren’t functioning properly, air won’t move as it’s supposed to. This directly affects the coil’s temperature balance and more often than not results in freezing.
A Glen Carbon homeowner recently noticed frost forming on the indoor unit and thought it was just condensation. After the AC completely shut down, a technician discovered a snapped blower belt was to blame. Without proper air circulation, the coil froze, and the entire system had to be shut off for repairs. Situations like this are frustrating, but they’re also preventable when the early signs of freezing are recognized and acted on quickly.
Consequences Of Ignoring A Frozen AC
When ice forms on your AC, brushing it off as a minor glitch can backfire. Letting your system keep running while frozen may lead to bigger problems inside the unit and inside your home. One of the first things homeowners might notice—aside from loss of cooling—is a higher than usual energy bill. A frozen coil limits how effectively your AC can exchange heat, forcing it to work longer and harder just to maintain the temperature you’ve set. That extra strain uses more electricity and can cause your monthly costs to spike.
Another concern is the long-term damage to major components. If the freezing happens frequently or isn’t dealt with quickly, the compressor can overheat or lock up. The refrigerant can no longer flow properly, which eventually causes system failure. In most cases, compressor damage is expensive to repair and may even require system replacement. It’s easy to ignore the signs during the early stages, like slightly reduced airflow or occasional frost, but doing so only increases the risk to the system over time.
Comfort also takes a hit. An AC that struggles to stay on or blows lukewarm air interrupts your daily routine, especially when summer is at its peak in Glen Carbon. It may take longer to cool down your living space, or the temperature might remain uneven across rooms. These results add more stress to your day and make it hard to rely on your home’s cooling system when you need it.
How To Prevent AC Freezing In Glen Carbon
Preventing a frozen AC starts with some simple checks and a habit of regularly maintaining your system. Local homeowners can stay ahead of many potential issues by building a few practices into their seasonal home routine:
– Replace air filters often: Dirty filters reduce airflow and are one of the top causes of freezing. Check and change them every 1 to 3 months, depending on use and indoor air quality.
– Schedule professional maintenance: Get a technician to inspect your AC unit before summer hits. Our professionals can test refrigerant levels, inspect coils, and clean blower parts to keep everything running right.
– Monitor refrigerant levels: If your system seems less effective or shows signs of freezing, it could indicate a slow refrigerant leak. Having the refrigerant charge tested and rebalanced prevents freeze-ups and protects your system’s key components.
– Evaluate thermostat settings: Avoid keeping the thermostat set too low for extended periods. Temperatures that are too cold may prevent the system from cycling off. Aim for something reasonable during hot Glen Carbon summers—setting it to the low 70s at most.
By taking these steps, you build reliability into your AC system. You also cut down the chances of needing a mid-season repair when cooling is most essential.
Know When To Call An AC Professional
There are times when even after changing filters and checking your thermostat, the unit still isn’t working right. If you keep noticing ice buildup, lukewarm air, or loud noises, the solution likely requires a deeper repair. These types of AC problems usually point to an internal issue that needs a trained eye and proper tools to fix safely.
Our technicians have seen it all, from system leaks and faulty blower motors to sensors that stop communicating with the thermostat. These aren’t problems you can solve without experience. Not knowing how to handle electrical components or refrigerant can lead to more serious damage or safety risks. That’s why calling our professionals early can save time, stress, and money in the long run. Diagnostic checks, proper part replacements, and expert adjustments all help restore the unit’s cooling performance.
When frozen coils become a repeated issue, it’s a sign something bigger is going on. Having our professionals evaluate the system ensures the root cause gets handled properly instead of just pushing the problem off until next summer. Timely service paired with the right knowledge makes a big difference in overall system life and comfort.
Keeping Your AC Efficient And Reliable In Glen Carbon
A frozen AC is more than a seasonal nuisance—it tells you your system needs attention. Glen Carbon homeowners who recognize the early signs and take action can stay ahead of costly repairs and sudden breakdowns. Doing simple things like replacing filters and managing thermostat settings helps a lot, but when problems go deeper, it takes skilled repair to get things back on track.
Reliable AC services in Glen Carbon aren’t just about comfort. They provide peace of mind that your home stays cool, energy-efficient, and protected from long-term damage. Making sure your AC remains in good shape each summer means more than just escaping the heat—it keeps your entire home environment running smoothly.
If your AC continues to struggle despite early fixes and regular upkeep, consider exploring AC services in Glen Carbon to address the root cause and maintain a cool, comfortable home environment. B & W Heating and Cooling, Inc understands the challenges of dealing with frozen AC units, and our professionals are ready to help restore your system’s optimal performance and prevent future breakdowns. For a quick estimate or to book a service visit, please contact us today.