What temperature should I set my A/C to in this Florida heat? Settings, maintenance and tips

Every summer — and spring and fall, in Florida — we face the eternal question: what temperature should I set my thermostat on?

Florida and the world have been suffering through a sweltering summer this year that has broken many heat records. We saw the hottest July since people have been keeping track and the second-hottest month ever, with multiple cities breaking their own records including Pensacola, Jacksonville, Tampa, Sarasota, Vero Beach, Fort Myers, Naples, Miami and Key West, based on their monthly average temperatures.

The heat index, also called the "feels like" or "real feel" temperature which uses temperatures and humidity levels to tell you what it's actually going to feel like out there, has been hitting over 115 in the shade for weeks, triggering daily excessive heat warnings from the National Weather Service. And it's likely going to stay hot through August and into September, according to the Farmer's Almanac.

It's hot out, is what we're saying.

So what temperature should you set your air conditioner on? Short answer: it depends.

What temperature should I set my a/c on in a Florida summer?

There isn't a magic number that everyone should use. It's a decision you make based on:

  • What feels comfortable to you and the other people in your household

  • Health conditions of people in your household

  • How well your place is insulated and otherwise protected against heat

  • What other cooling methods you use (floor fans, ceiling fans, closed curtains/shades, etc.)

  • How much you're willing to pay on your electric bill

The first and last ones are key. If you can afford it, run your a/c as low as you want. Just be prepared for considerably higher bills and likely more air conditioner maintenance and repairs.

Katarina Alvarez, a senior communications strategist for Florida Power & Light, said a one-degree increase in thermostats could save between 3-5% on cooling costs. The less your a/c has to work, the lower your bill.

So set your thermostat to the highest temperature that you can remain comfortable in and can afford, and look for other ways to cool off your place.

Should you set your temperature to 78 degrees?

For a long time, 78 degrees has been the number everyone drops in their "stay cool" guides. Which is fine for some people, and for lizards.

When the media and electric utility companies promote 78 degrees they often refer to ENERGY STAR, a program run by the Environmental Protection Agency and the U.S. Department of Energy that has become synonymous with energy-efficient appliances. But ENERGY STAR doesn't recommend any specific temperature.

“ENERGY STAR does not assert that any particular temperature setting is good for households,” the EPA said in an email to The Palm Beach Post.

Should I turn my air conditioner off at night and open the windows?

In the Florida summer, probably not a good idea unless you just like the heat.

Temperatures don't drop that much in the Sunshine State overnight and letting the place heat up means your a/c will have to start from scratch in the morning. It also means letting in a lot of moist, hot air that will get absorbed by the carpeting and furniture upholstery, which means an uncomfortable house and the increased possibility of mildew.

Should I turn my air conditioner off if I leave for work or vacation?

The work your a/c will have to do to bring the temp back down to liveable when you get home from work may not be worth what you save by turning it off.

Air conditioning also helps reduce humidity in your house, and that helps keep mold and mildew in check. There are also your pets to consider. Your dogs and cats don't like the heat any more than you do, and they have fewer ways to cool off.

When you're out of the house for an extended amount of time, FPL recommends setting your thermostat to 85 degrees with the fan on "auto."

Keep the home cooler for people more susceptible to heat

Older adults are more prone to heat stress, according to the Centers for Disease Control. They don't adjust as well to temperature changes, they're more likely to have a chronic medical condition that changes their normal responses to heat, and they're more likely to take prescription medicines that affect the body's ability to control its temperature.

Older people also are more prone to Alzheimer's disease and other dementia-related illnesses, and scorching heat can be even more dangerous for individuals who may not notice that they're overheating, may not understand what it means, may have impaired judgment, or may not be able to tell anyone about it.

"Summer can be extremely dangerous for those with Alzheimer's in Florida," Julie Shatzer, Vice President of Programs for the Florida chapters of the Alzheimer's Association, said in an email. "Symptoms of overheating can be difficult to detect in those with Alzheimer's and other dementia since they can be similar."

How can I keep the bills under control while running my a/c nonstop?

Turning off the a/c isn't much of an option when overnight temperatures stay in the high 70s and it doesn't save you much money since your a/c will have to work that much harder in the morning to catch up. But there are plenty of ways to give your air conditioner less to do.

  • Use a programmable or smart thermostat. Raise the temps to 78-82 or more while you're at work, away or during the night (if you can).

  • Start a fan club. Fans don't cool the air, but they do make you feel better as the moving air cools your skin and helps your body evaporate sweat. Turn on your ceiling fans and put some smaller fans around the place to keep your air circulating. Be sure to turn them off when you leave the room for more savings.

  • Change your a/c filter every month. Easy to do, and it does wonders to help your a/c help you. Dirty or clogged filters make a/c units work harder. Don't use a heavier filter than you need. Some promise to filter out all viruses, contaminants and pet dander, but they also choke airflow and may make your a/c have to work harder. When you get your unit serviced, ask the technician for a recommendation to meet your needs.

  • Close curtains and blinds. Keeping direct sunlight out of the house helps a lot to keep the inside from heating up.

  • Keep vents clear. Blocking a/c vents blocks airflow. You want airflow so the room will cool to the temp the thermostat is set at.

  • Check your insulation and weatherstripping. If heat is getting into the house (and cool air is getting out) your a/c has to work harder. Check the weatherstripping around windows and doors and make sure your attic is insulated.

  • Close doors and vents of rooms you're not using. Why pay to cool a room you don't need to? Close the vents in your guest room or utility room or any space you don't use regularly and keep the door closed. An exception: if the room connects other rooms you do use, leave the doors open to keep airflow moving through the area.

  • Cut your electric bill elsewhere. Unplug equipment and appliance that uses energy even when turned off, such as TVs, air fryers and video game consoles. Turn lights off if you're not using them. Lower your water heat temp to 120. Use cold water in the washing machine. Use smaller appliances in the kitchen. Basically, everything your parents used to tell you to do. Sorry.

  • Keep your a/c maintained and healthy. A/C repair companies are busy in the summer, and if yours breaks down they might not be able to get to you right away. Keep yours in good shape before it starts to make weird noises.

How often should I get my air conditioner maintained?

ENERGY STAR recommends once a year, in the spring, but Floridians might want to go twice, especially if you live near the coast.

What can I do to maintain my air conditioner?

  • Change or clean the air filter every month.

  • Keep leaves, shrubbery and other debris at least 18 inches away from the outdoor unit to avoid blocking the airflow. Don't cover the condenser coil outside to make your house look prettier.

  • If you have an outdoor drain, keep it clear and unclogged.

How can I tell if my air conditioner needs to be replaced?

Your a/c needs to be repaired if it stops working (obviously), makes loud noises while running, or can't keep your house cooled to at least 78 degrees. But it might need to be replaced if it's over 10-15 years old, your energy bills have skyrocketed and you keep having to get it fixed

Older units have other issues, such as increasingly scarce parts or outdated coolant. The U.S. ceased production of Freon in 2020 and older units used R-22 Freon, which is getting tougher to find. And newer systems are more energy efficient.

This article originally appeared on The Daytona Beach News-Journal: Best Florida summer air conditioner temperature? It depends