Nothing saps the joy from a summer day quite like realizing your air conditioning unit isn’t cooling properly. Whether your home feels more like a sauna than a sanctuary, or your AC seems to be blowing lukewarm air no matter how low you set the thermostat, there are a few usual suspects that could be to blame. Fortunately, most of them are fixable—and some can even be prevented with a little routine maintenance.
Related: Spring HVAC Updates: Prepare Your Equipment for Warmer Weather
Let’s explore the top three reasons your AC isn’t cooling properly and what you can do to get that refreshing blast of cool air back in your life.
1. Dirty Air Filter
Why It’s a Problem:
When your air filter is clogged with dust, pet hair, and other debris, it restricts airflow. That means your system has to work overtime to circulate air—and even then, it’s not moving enough to cool your home efficiently. A dirty filter can also cause other parts of your system, like the evaporator coil, to work harder and potentially freeze up (more on that later).
How to Fix It:
Check your air filter every month during heavy-use seasons like summer and change it at least every 1-3 months, depending on the type of filter and how much dust and dander your household generates. If your air conditioning unit is not working properly, the filter should be the first thing you check. Replacing it is a simple, inexpensive fix that can make a world of difference.
2. Low Refrigerant (a.k.a. AC Refrigerant Leak)
Why It’s a Problem:
Refrigerant is the magic ingredient that actually cools the air in your home. If your system is low on refrigerant, it’s often because of a leak—not just because it “ran out.” When your refrigerant levels are too low, your AC can’t effectively cool the air, and you might notice warm air coming from your vents, higher energy bills, or a system that runs non-stop without ever reaching the set temperature.
How to Fix It:
This one’s not a DIY job. If you suspect a refrigerant leak, you’ll need a licensed HVAC technician to inspect your system, find the leak, repair it, and recharge your refrigerant levels. Running your system with low refrigerant can damage the compressor and lead to a broken AC that’s far more expensive to fix. Catching this issue early can save you time, money, and a major headache during the peak of summer heat.
3. Frozen Evaporator Coil
Why It’s a Problem:
Ironically, when your evaporator coil freezes, your AC actually loses its ability to cool. This component absorbs heat from inside your home, and when it’s coated in a layer of ice, it can’t do its job. You might notice your system running but not blowing any cool air—or air at all.
How Does This Happen?
A frozen evaporator coil is often caused by—you guessed it—a dirty air filter or a low refrigerant level. Both restrict airflow and/or affect the pressure in the system, causing moisture to freeze on the coil.
How to Fix It:
First, turn off your AC to allow the coil to thaw completely. Then check your air filter and replace it if it’s dirty. If the coil keeps freezing up, it’s time to call in an expert to check for a refrigerant leak or airflow issues within your system.
The Importance of Regular Maintenance
So many of the issues that lead to an air conditioning unit not working stem from one key thing: lack of preventative maintenance. We get it—your AC is one of those “out of sight, out of mind” systems we all expect to just work. But like any hardworking machine, it needs a little TLC to stay in top shape.
Here’s What Regular Maintenance Can Help You Avoid:
- Poor airflow from a dirty filter
- Frozen evaporator coils
- Higher energy bills due to inefficient cooling
- System strain that leads to early breakdowns
- Refrigerant leaks that quietly kill your system
Scheduling a professional HVAC tune-up at least once a year can prevent most common cooling problems and extend the life of your system.
Related: How HVAC Preventative Maintenance Saves Heating Costs and Prevents Hassle
We’re Here to Help
If your air conditioning unit is not working and your home is not cooling properly, don’t sweat it. Our expert team is ready to diagnose the problem, provide efficient repairs, and get your home cool and comfortable again. From dirty evaporator coils, to frozen evaporator coils, to AC refrigerant leaks, we’ve seen it all and fixed it all.
And if everything’s running smoothly now? Great! Let’s keep it that way. Regular maintenance is your best defense against a broken AC unit. Schedule your seasonal check-up today and enjoy peace of mind all summer long.
Stay cool—your comfort is our priority.