Record heat is pushing air conditioners harder than they were designed for and leaving people sweating. The impulse, of course, is to crank down the temperature on the air conditioner. But that not only cranks up your utility bills, it also puts a strain on HVAC systems, which are not built for extreme demands.
“[T]hese extreme temperatures present a significant challenge to AC systems, which engineers and installers say are really only designed to keep indoor temperatures about 20 degrees cooler than outside,” according to National Public Radio.
Such demand on a home’s AC makes the unit run less efficiently, which forces the AC to run nonstop, one expert tells NPR. But installing an oversized air conditioner to cool the house better during a few heat spells isn’t the answer, as it’s too big to do the job efficiently the rest of the time.
What’s an overheated household to do? Follow these tips to make your AC run as efficiently as possible and your home feel cooler.
1. Get smart with heat-generating appliances
Kitchen appliances — particularly ovens and stoves — add heat to already oppressive summer days. Use your stove and oven at night, if possible. Think about temporarily changing a few habits, too: Make meals with the microwave oven. Or, eat cool foods that don’t need heating.
The oven and range are two obvious appliances that heat up your home. But there are others. The dishwasher and washing machines also give off heat and moist air, contributing to a muggier, warmer home, says Tom’s Mechanical, of Arlington, Texas. See if running them less often, and at night, helps. Also, to reduce indoor humidity (and save energy) use the dishwasher’s non-heated dry cycle.
2. Replace incandescent bulbs
Next to LED bulbs, the older incandescent bulbs are energy wasters.
“[Y]ou can feel the energy incandescent bulbs waste in the form of the heat they emit,” says Tom’s Mechanical.
By replacing incandescent bulbs with LEDs you’ll save money over the long run on energy bills and help cool your home at the same time.
3. Stay on top of AC maintenance
Increase your comfort at home by following these two steps:
- Keep a close eye on your air conditioner’s filter, changing it regularly. By letting an AC filter become clotted with dust, you’re stopping the free flow of air through the AC system. This, in turn, cuts into the efficiency of the air conditioner, says CNET, explaining how to tell if your filter needs changing.
- Keep your outdoor heat exchanger’s coils clean. Dusty coils make it harder for the heat exchanger to work efficiently. “A lot of people do not maintain their basic unit. If you can keep a real good clean outdoor coil, it definitely helps the air conditioner remove the heat,” James Barry, of Doctor Cool & Professor Heat, in League City, Texas, tells NPR.
4. Stop fiddling with the thermostat
Turning down the thermostat setting in response to heat waves doesn’t get the most out of your equipment and thus can drive up your utility bills.
The most efficient move is to keep your thermostat set at a consistent, low level all the time, Srinivas Garimella, professor of mechanical engineering at Georgia Institute of Technology (Georgia Tech) tells NPR.
5. Use outdoor window coverings
Various window attachments — awnings, shades, shutters and screens — can be installed on the outside of windows to help bring down interior temperatures.
Outdoor shades and awnings “can improve energy performance, create a more comfortable environment, reduce glare, provide privacy and enhance the appearance of your home,” says the Attachments Energy Rating Council (AERC), an industry group.
Awnings can be used to shade individual windows or an entire side of a house. (Retract them in winter to help warm the home.)
Awnings can reduce solar heat gain by up to 65% on south-facing windows and by as much as 77% on west-facing windows, according to the U.S. Department of Energy (DOE). Newer awnings use water-repellant synthetic materials more durable than awnings of yore, which needed frequent recovering.
Reflective films, another hot-weather solution, are installed on window glass to direct much of the sun’s heat away from a home while blocking UV light from entering, according to 3M. Depending on the film and the window type, it may be installed on the inside or outside of the glass.
Silver, mirror-like film repels heat best, says Consumer Reports. Also, film stands to reduce more heat on windows facing east and west.
Reflective film is not without problems, though: It can be difficult to clean and may even affect your view, Consumer Reports says.
6. Use inside window treatments
Interior window treatments — shades, screens and even blinds, curtains and drapes — also can help cool a home.
Closing curtains can help cool the interior, save money on utility bills and lessen the wear and tear on your HVAC system, according to North Georgia Replacement Windows in Roswell, Georgia.
Here’s a simple technique I’ve used. It costs nothing:
- Keep curtains, drapes and other window coverings closed on hot mornings to retain cool air from the night.
- Do the opposite at night, allowing cool night air into the home.
Your window coverings’ heat resistance depends on the material, weave (open or tight) and color.
“Studies demonstrate that medium-colored draperies with white-plastic backings can reduce heat gains by 33%,” according to the DOE.
Cellular shades — depending on the product — can help keep heat in winter and, in summer, cool the home.
“Cellular shades can reduce unwanted solar heat through windows by up to 60%, reducing the total solar gain to 20% when installed with a tight fit,” says the DOE.
7. Make smart use of fans
Fans are a time-honored way to cool off. Long before HVAC was a thing, people were waving palm fronds and paper fans to generate a cooling breeze.
Ceiling fans can move a lot of air, helping to create a sensation of coolness as the breezes graze your skin. Table fans, box fans and standing floor fans also help in the same way. Just remember that these appliances suck up a fair amount of electricity. Turn them off when you leave the room.
Tip: Remember to adjust the setting on your ceiling fan so the blades rotate counterclockwise, pushing air down, explains Home Depot. In winter, switch the direction of the blades.
Use the exhaust fans in bathrooms and kitchen when bathing and cooking to manage humidity in the home and prevent mold and mildew. Also, leave these fans running for 15 to 30 minutes after you shower or bathe to help prevent mold and mildew growth in bathrooms, says Tom’s Mechanical.