When you live in St. Augustine, your air conditioner isn’t just a luxury, it’s essential. So, when your AC suddenly stops cooling and you discover ice building up on the unit, what caused it, what should you do, and how can you prevent it from happening in the future?
Easy answer — Call Glacier Heating and Air Conditioning at 904-540-8199 to find out.
Believe it or not, a frozen AC is a common issue in Florida’s hot, humid climate. The good news? It’s usually preventable with the right care and maintenance.
At first glance, ice forming on your AC in the middle of summer seems backwards. But it’s typically caused by one simple issue: restricted airflow or low refrigerant levels, both of which disrupt the system’s ability to absorb heat properly.
Here are the most common culprits:
1. Dirty Air Filters
A clogged air filter restricts airflow, preventing warm air from circulating over the evaporator coil. Without enough warm air, the coil gets too cold and freezes over.
2. Blocked or Closed Vents
Closing vents in unused rooms may seem like a way to save energy, but it can actually throw off your system’s balance and reduce airflow—leading to ice buildup.
3. Dirty or Rusted Evaporator Coils
Over time, dust and debris can accumulate on your evaporator coil, insulating it and reducing its ability to absorb heat. Rust can also be problematic as it can lead to corrosion and leaks, which in turn can cause the refrigerant levels to drop.
4. Low Refrigerant Levels
If your system has a refrigerant leak, it can lower the pressure inside the coils, causing them to become too cold and freeze.
5. Fan or Blower Issues
If your blower fan isn’t working properly, it won’t move enough air through your system — another common cause of freezing.
Signs Your AC May Be Freezing Up
Watch for these warning signs:
- Weak or warm airflow from vents
- Ice visible on indoor or outdoor components
- Unusual hissing or bubbling sounds
- Sudden increase in energy bills
- AC running constantly without cooling effectively
If you notice any of these, it’s important to act quickly before further damage occurs.
How to Prevent Your AC from Freezing
The best way to avoid a frozen AC is with simple, consistent maintenance:
Change Your Air Filter Regularly – In Florida, filters should typically be changed every 1–3 months, especially during peak cooling season.
Keep Vents Open and Unblocked – Ensure all supply and return vents are open and free of obstructions like furniture or curtains.
Schedule Routine Maintenance – Professional tune-ups help catch issues like dirty coils, low refrigerant, or worn components before they lead to freezing.
Check Your Thermostat Settings – Avoid setting your thermostat too low for extended periods, especially at night. This can overwork your system.
Keep the Area Around Your Unit Clean – Clear away debris, leaves, and dirt around your outdoor unit to promote proper airflow.
If you discover ice on your AC:
- Turn off the system immediately to allow it to thaw
- Switch the fan to “ON” to help speed up the process
- Check and replace your air filter if needed
- Call a professional if the issue persists
Running a frozen AC can cause serious damage to the compressor which is one of the most expensive components to replace.
At Glacier Heating & Air Conditioning, we understand how important reliable cooling is for your home and family. Whether it’s routine maintenance or emergency repairs, our experienced team is here to keep your system running efficiently all year long.
If your AC is freezing up—or you want to prevent it from happening in the first place — don’t wait. Contact us today to schedule your biweekly maintenance and stay comfortable no matter how high the temperature climbs.
Not on a maintenance plan yet? Don’t worry, we can get you signed up and on the calendar for service right away.
Learn more. Call us today at (904) 540-8199
Voted Best of St. Augustine two years in a row. We take pride in serving our community with quality heating and air conditioning services.