It’s the middle of July and your house feels less like a retreat and more like a brick oven. The A/C’s humming, but the air inside? Still stuffy, sticky, and somehow warmer than your neighbor’s barbecue grill.
Before you resign yourself to melting or run up a service bill, here’s a collection of practical (and sometimes surprising) tricks to try when your A/C can’t quite keep its cool.
Check the Basics First
Start with the small stuff—sometimes the fix is easier than your heat-fogged brain expects. Make sure your thermostat is actually set to “cool” and not “fan.” It sounds silly, but even the most diligent homeowners have missed this.
If your air filter is clogged with dust and pet hair, your system can’t breathe properly, so swap it out. Changing your filters every 1-2 months, especially in summer, is one of the simplest ways to keep air moving and temperatures dropping.
Test Your Vents and Windows
Walk through every room—are your vents open and unblocked by furniture, curtains, or storage boxes? You’d be amazed how many “hot rooms” owe it to a closed or hidden vent.
While you’re at it, check your windows for sneaky drafts or spots where hot air slips inside. Cover sunny windows with blackout curtains or blinds during the day. Blocking out sunlight can keep rooms several degrees cooler—and your stressed-out system will thank you.
Give Your A/C a Break with Some Backup
If your A/C still isn’t cutting it, help it out. Switch on ceiling fans to keep cold air circulating. Use box fans to draw hot air out by placing them in open windows (facing outward) in the evening. Keep doors closed in rooms you’re not using so your A/C has less work to do. Take a quick break from heat-creating chores—baking, drying laundry, or long, steamy showers can push the temperature higher indoors.
Don’t Skip the Heat Load Calculation
If you’ve tried all the hacks and your system just isn’t keeping up, the problem could be that your unit is actually the wrong size or strength for your home. This is where something called a heat load calculation comes in, which factors in everything from your home’s square footage to insulation, number of windows, and even which way your house faces.
If your A/C is too small, it will run (and run) with barely any effect. Too big, and it’ll shut off before it’s handled the humidity, leaving you with clammy, sticky air.
Don’t Be Afraid to Call for Backup
If your system is still stubbornly warm, strange sounds or even puddles around your indoor unit could signal a bigger problem. Refrigerant leaks, busted compressors, or clogged condensate lines aren’t DIY fixes. Bring in a trusted technician to get your system back on track.
Summer heat waves don’t have to mean sweating it out all season. A little troubleshooting, some strategic know-how, and a heat load calculation if things don’t add up can mean the difference between a house that bakes and one that feels like a breath of fresh, cool air. Stay cool—and remember, sometimes the smartest move is to ask for help.