How to Keep Your AC Running Strong During a Heat Wave

6/19/2025

When Central Iowa turns into a furnace and the heat index starts flexing into triple digits, your AC is no longer just a comfort. It’s a lifeline. But extreme temps can also push your system to its limit. To keep your home cool and your system from breaking a sweat, here’s how to run your AC smarter during a heat wave.

1. Don’t Crank It. Set It and Trust It.

It’s tempting to drop your thermostat to 65° the second you walk into a wall of humidity. But that just forces your system to work harder without cooling your home any faster. Set your thermostat to a reasonable temp, around 72° to 75°, and give your system time to gradually get there.

2. Utilize Your Ceiling Fans (Correctly!)

Ceiling fans don’t cool the air, but they create a wind-chill effect on your skin, making you feel cooler. During a heat wave, ensure your ceiling fans are set to spin counter-clockwise. This pushes air down, creating a refreshing breeze. Remember to turn them off when you leave a room, as they only cool people, not spaces.

3. Close the Curtains and Block the Heat

During peak sun hours, roughly 10 AM to 4 PM, keep curtains, shades, and blinds closed. Every bit of direct sunlight adds more heat your AC has to fight.

4. Avoid Big Indoor Heat Sources

Running your oven, dryer, or even taking long, steamy showers during the hottest parts of the day will raise your indoor temp fast. Opt for grill dinners, delay laundry, and turn on bathroom exhaust fans to keep heat and humidity at bay.

5. Understand and Manage Humidity (Beyond Just Temp)

Your AC is a powerful dehumidifier too. In Central Iowa’s humid summers, managing indoor humidity is just as crucial for comfort as managing temperature. High humidity makes you feel hotter, even at a comfortable temperature, and can make your AC work harder. Ensure your AC is running long enough cycles to adequately remove moisture. If your home consistently feels sticky despite the temperature being cool, consider running your fan setting to ‘Auto’ rather than ‘On.’ ‘Auto’ allows the fan to turn off with the compressor, letting moisture drip off the coil, while ‘On’ can reintroduce some humidity into the air.

6. Check and Replace Your Air Filter

Your system’s airflow is its oxygen. A clogged air filter can choke your system and reduce efficiency by up to 15 percent. During high-demand weeks like this, check your filter even if it’s not due yet.

7. Don’t Shut Vents or Close Off Rooms

It seems logical to close vents in unused rooms to “save” air for the rest of the house. But your HVAC system was designed for balanced airflow. Closing vents can create pressure imbalances and actually make things worse.

Extreme heat puts every system to the test. Following these tips can help yours perform at its best when you need it most.

The dog days of summer shouldn’t be rough. If you experience an issue with your AC, we’re just a click or a call away. And we always Fix It Right or It’s Free!

515-657-6634Schedule Online

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