Summer’s finally here, and if you’re like many Minnesotans, you may be struggling to find a comfortable indoor temperature — especially on the hottest days. You don't want to set your thermostat so cold you have to grab a blanket, yet you don't want to be hot and sticky, either. To help, we asked experts what's the best temperature to set your thermostat at to keep comfortable in the summer.
The Outdoor Temperature Factor
Before you turn on your AC for the season, be sure that the outside temps are consistently above 60 degrees. Running your air conditioner when the outside temperature is below that can cause major damage to your unit.
“It’s very bad for the unit as it actually works too efficiently and cools the indoor too much,” says Keith Hill, technical support and training manager for Minnesota Air. “The indoor coil will quickly drop below 32 degrees Fahrenheit and then the freezing starts. Frost and ice forms on the coil, blocking the airflow, and if it’s not discovered soon, may lead to compressor damage or even internal failure.”
Even if you have reasons to want to run your air conditioner on a milder day, instead of opening a window or using fans (allergies, windows painted shut, home security, etc.), just make sure it’s above 60 degrees. And remember to turn off your AC on those nights when the temperature drops below 60 degrees.
The Indoor Temperature Factor
It can be tempting to set your summertime thermostat to the temperature setting that was typical for your home in winter — such as 68-70 degrees. However, running your unit below 70 can also create problems.
“Do not run the AC unit below 70 degrees indoors for the same reasons — it can freeze the evaporator coil,” he says. With some systems, that threshold might be 65 or 68 degrees. It depends on other factors, too, including airflow and indoor humidity. That’s why never going below 70 degrees is a safe practice.
“I’m not sure why anyone would operate his or her AC so cold, but we do hear about it,” Keith says. “Maybe they think it helps an allergy condition or they like to wear sweaters in the summer, but it’s not good for the equipment, and it will drive up your energy bill.”
Humidity is More Uncomfortable than the Temp
While we often focus on heat, it’s really humidity that makes us feel sticky and sweaty. That’s why the temperature can actually be higher if the humidity is lower. “My advice is always to pick the highest set point where you are comfortable. Realize it’s not all about the temperature, it’s also the humidity,” he says.
If you have a dehumidified home, you may be able to set your thermostat even higher. Not only will you still feel quite comfortable, but you’ll save on energy costs, as well. You may need to do a little experimentation, but a general rule of thumb is to start by setting your thermostat between 72-76 degrees in the summertime. Then, you can adjust up or down to set a temperature that works for all family members.
Don’t Adjust the Temp After Strenuous Activity
It’s tempting, but don’t touch that dial (or buttons) if you’ve been exercising, working outside, or doing some other strenuous tasks. “We tend to head to the thermostat as we wonder why we are too hot, and then see that the temp is where it should be,” Keith says. “But too often, the temptation gets the better of us and we tweak it just a bit.”
Keith recommends resisting that urge. “Trust the thermostat to do its job, remember why you set it where you did in the first place, and give it some time for you to cool down.”
Don't Turn the Temp Down to Cool Faster
One of the biggest no-no’s is cranking your AC to a lower temperature just to get your home to cooler faster. The Department Of Energy says that doing so “will not cool your home any faster and could result in excessive cooling and unnecessary expense.” Keep the thermostat at your normal, ideal setting and your body will cool normally.
Invest in a Programmable Thermostat
A programmable thermostat saves energy and money in the summer because it can turn on your AC when you’re home and turn it off or have it run at a higher temperature when you’re away. Some of the newer models, like Carrier’s COR thermostats, are made to be intuitive and keep you comfortable beyond what a regular model can do. They also provide better humidity control, maximizing comfort without lowering the cooling temperature.