When your air conditioner starts icing up, it feels like the exact opposite of what should happen on a hot day. Instead of cooling your home, it slows down, works harder, and might even shut off completely. This kind of issue doesn’t always mean disaster, but it does indicate something isn’t working the way it should. At Waterbury Heating & Cooling, Inc. in Sioux Falls, SD, we’ve helped many homeowners determine why their AC freezes.
Blocked Airflow Makes It Worse
When your air conditioner can’t breathe, everything starts to go wrong. If the filter is dirty or the vents are blocked, less air gets across the coils. That might not seem like a big deal, but the coils need steady airflow to stay warm enough during use. Without it, they drop below freezing.
Moisture from the air starts to build up and freeze on the coils, causing issues. Changing your air filter once a month during the hot season helps. So does checking for closed vents or furniture that might be sitting too close to one. When airflow returns, your AC has a better chance of running normally again.
Low Refrigerant Makes the Coils Too Cold
Your AC requires the right amount of refrigerant to work correctly. This liquid absorbs heat from the air and moves it outside. But when refrigerant leaks out, the pressure in the system drops. That lower pressure leads to lower temperatures inside the evaporator coil.
If the coil gets too cold, condensation freezes on it. The unit keeps trying to run, but it can’t pull in enough heat to prevent the ice from spreading. If your AC is low on refrigerant, it needs more than a refill. A technician must find the leak, fix it, and recharge the system. Otherwise, you’ll end up with another frozen coil not long after.
Dirty Coils Can’t Do Their Job
Even if you keep the filter clean, the coils can still collect dust and gunk. If that dirt builds up, it stops the coil from pulling heat out of the air. The coil stays too cold, and the water vapor around it freezes instead of draining away. This turns into a layer of ice, which makes it harder for the system to cool your home.
If you spot frost building up on the outside line or notice a drop in air temperature, a good cleaning makes a big difference. You shouldn’t try to scrub the coils yourself with harsh tools. Instead, use a soft rinse with coil cleaner or ask a professional to get things back on track.
Thermostat Settings Can Confuse the System
Sometimes, the cause of your AC freezing is a simple issue. If you set your thermostat much lower than needed, your AC works nonstop to catch up. That nonstop running can cause the coils to freeze. Let’s say you set the thermostat to 65 degrees Fahrenheit when the outside temperature is 95 degrees. Your system can’t always hit that number, so it runs continuously to try to read your set temperature.
Pair that with any airflow or refrigerant problem, and ice develops on the coils. It helps to pick a temperature that makes sense for the conditions. Somewhere between 72 and 78 degrees keeps your space comfortable without overloading the system. If your thermostat has a fan mode, leaving it on “auto” instead of “on” can help prevent the cool air from sitting on the coils too long when the compressor isn’t running.
Drainage Problems Add to the Mess
When drain lines get clogged, things back up into the pan and coil area. Standing water in a warm, dark area can lead to the development of mold or algae. More importantly, it can cause the coil area to remain damp and cold, which invites icing in some units.
This can cause a shutdown or water to leak into system areas where it doesn’t belong. Checking the drain line and keeping it clear helps your AC stay dry where it should be. A shop vac can sometimes help remove small clogs from the outside drain line, but if that doesn’t work, it’s time to ask for help.
Unfreeze Your AC Today
Whether it’s a clogged filter or a mechanical issue, repairing it early helps you avoid bigger expenses down the road. We also offer heating repair, ductless mini-split installation, and indoor air quality services to keep your home comfortable. If your AC keeps freezing, it’s time to schedule a visit with our professionals at Waterbury Heating & Cooling, Inc..
