But you shouldn't run your AC if the temperature is below 60°F. Heat pumps: Modern heat pumps are effective at around 25 to 30°F. Ductless mini-splits: Avoid using the cooling function when temperatures fall below 60°F.
HVAC manufacturers typically advise users not to run their units for extended periods if the temperature is below 65 degrees Fahrenheit.
Setting your air conditioning to 72°F is generally considered a comfortable indoor temperature for many people. It strikes a good balance between comfort and energy efficiency, making it a popular choice for residential settings.
What should my AC be set at if it's 90 degrees outside? If the outdoor temperature is 90 degrees, it's recommended to set your thermostat between 75-78 degrees.
Quick answer: The ideal house temperature is room temperature, which ranges from 68 to 78 degrees F, though this may vary from season to season. In winter, the average room temperature is generally 62 to 68 degrees, whereas in the summer, the average temperature is 72 to 78 degrees.
If you set your thermostat in the 80s, the air conditioner won't run enough to effectively dehumidify your home's air. Here in the Tennessee Valley, we have extremely humid weather in the summertime. If your thermostat is set at 80+ degrees, then the humidity inside of your home can easily get up above 70%.
To maintain a comfortable indoor environment during the summer, the American Society of Heating, Refrigerating & Air Conditioning Engineers recommends a range of 73 to 79 degrees Fahrenheit.
Most people work better and are more productive when with a temperature setting in the 72–74-degree range. This setting is low enough to keep the house cool and dry and keep you and the kids awake during the afternoon hours.
Just because the outdoor temperature is above 100, the Ideal temperature to set your AC unit to doesn't change — it's 78 degrees. Higher temperatures in the home are to be expected when the weather is hotter than usual, but your thermostat can still be set the same as if it were a lower temperature outside.
Your AC might not cool properly due to thermostat issues, an undersized unit, or extremely high outdoor temps—so check those first. Keep an eye on airflow—replace clogged filters every 3 months, and make sure vents and ducts aren't blocked for efficient cooling.
U.S. Department of Energy research suggests that setting your programmable thermostat to 78 during the summer months is the best way to save money on your cooling costs while maintaining a comfortable temperature.
Summer Air Conditioner Settings
In the summer, experts say the thermostat for your air conditioner should be set to at least 78°F during the day when people are at home.
Clean the Thermostat
Sometimes, when the room temperature doesn't match the thermostat setting, the problem could be dirt buildup on its interior parts. A dirt coating around the inner components may create excess heat and cause the thermostat to give the wrong readings.
Do not set your thermostat below 70 degrees as it will not cool any faster and could freeze up the system causing more problems. Understand that there is generally a 20 degree difference between indoor air and outside temperatures.
Temperatures Above 100 Degrees Fahrenheit
When temperatures outside become higher than 100 degrees Fahrenheit, the air conditioning system can consume more energy and begin to malfunction or fail. Most air conditioning systems are designed to function with outside temperatures of 100 degrees or less.
When setting your thermostat, most homeowners find 72 is a good temperature for air conditioning. However, you may need to adjust that setting based on weather conditions. The bigger the difference between indoor and outdoor temperatures, the higher your energy bill will be.
For many of us, 70 degrees is the ideal indoor temperature, but when it is close to 100 degrees outside, your AC unit will be working quite hard to meet these expectations. Consider setting your thermostat at 75 degrees to 80 degrees in your home if the outside temperature is approaching triple digits.
Recommended AC Temperature for Sleeping
The Sleep Foundation says 65° is the best temperature for sleeping. However, if you prefer a slightly warmer or cooler room, that's okay, too. The recommended range is 60–68°, so there is some wiggle room.
During a heatwave, we recommend that you don't lower the AC's setting below 68°F. This is already quite chilly for most people, and many would consider it too cold. An air conditioner set this low risk of its coil freezing—and that's bad news because it indicates that the air conditioner is overworked.
In most cases, especially in residential applications, you should not run your air conditioner when outdoor temperatures are below 60 degrees.
Keeping in mind both energy efficiency and comfort, the best thermostat settings for summer are 76° when you are home, 80-85° when you are away and 72° at night. Then use ceiling fans in the rooms you are in to feel up to 4* cooler. Here's more on why these thermostat settings are the best.
On work days, you can set the temperature a few degrees higher when you usually leave the house, and then have it start cooling down to your ideal temperature 30 minutes before you return. If you don't have an ideal temperature, the DOE recommends using a baseline of 78 degrees when at home for the most savings.
The suggested temperature setting by Energy Star is 85 degrees when no one is home. However, if you live in a region of the country with consistently high humidity levels, consider setting the thermostat closer to 80 so your HVAC system doesn't run as frequently.
For most people, 75 degrees is too hot to sleep, per the National Sleep Foundation. But the new study found that in people 65 and up, sleep efficiency only started to decrease when temperatures were above 77 degrees.
Hence, to take a temperature closer to 24 degrees is considered to be healthier for individuals in tropical regions like India. The ministry says that, as per the comfort chart, temperatures up to 25 degrees are quite comfortable for human body, along with the desired humidity and air movement values.