The recommended rule of thumb for summertime is to set the temperature to 78 degrees Fahrenheit when you're home and higher when you're away. In general, set it to 82 degrees Fahrenheit when you're asleep and 85 degrees Fahrenheit when you're away.
Recently, the federal government released new recommendations for energy efficiency. According to these federal guidelines, during the summer you should set your thermostat at 85F during the day when no one is home. They also recommended setting your thermostat at 82F at night.
According to the Department of Energy1, 78° Fahrenheit is the sweet spot for air conditioners to balance energy savings and comfort when people are at home and need cooling.
When temperatures exceed 100 degrees Fahrenheit outside, setting your air conditioning (AC) to around 75-78 degrees Fahrenheit is generally considered efficient. Here are some reasons for this recommendation:
In short, the 20-degree rule of air conditioning states that you should always keep your AC unit at no more than 20 degrees lower than the outside temperature. It means that, if the outdoor conditions are at 95 degrees, you should set your thermostat at no less than 75 degrees.
The lowest outside temperature at which to run your AC is typically around 60-65 degrees Fahrenheit. At temperatures below this range, your air conditioner might not operate efficiently, causing increased energy consumption and potential strain on the system.
What temperature should you set your air conditioner? According to the Environmental Protection Agency, your AC temperature should be set at 78 degrees Fahrenheit for peak comfort and energy efficiency. Then, when you're at work set the temperature seven degrees higher.
The ideal temperature for a house depends on the season. In the summer, it's around 72 to 78 degrees Fahrenheit; in the winter, it's around 62 to 68 degrees Fahrenheit.
Since 72 degrees is generally agreed upon to be an ideal indoor temperature, most people would probably still feel comfortable setting their AC units slightly higher than this, perhaps at around 75.
For the most efficient performance, set the thermostat 20 degrees lower than the temperature outside. On a 100℉ day, set it to 78℉ to 80℉ to manage utility costs. If there's a lack of airflow, the filter may need to be changed or AC vents cleaned.
What is the Best Thermostat Setting for Summer Air Conditioner Use? Energy Star recommends the following thermostat temperatures for your air conditioner in the summer: 78°F during the day if people are home. 82°F at night if people are home.
While the standard room temperature of 72 degrees Fahrenheit is commonly favored by many, others argue for higher settings, particularly when it's hotter outside.
There are benefits to having your air conditioner set to “auto” and “on.” The benefits of the “auto” setting include higher efficiency, lower energy bills, better humidity control, less wear and tear on some components, and quieter running.
Most experts agree that a temperature as high as 85 degrees Fahrenheit is safe for your home while you are at work or away on vacation.
A dirty air filter
Your air filter is designed to trap contaminants in the air before it gets pulled into the AC system. But over time that means that your filter gets dirty and clogged. And if a dirty filter isn't replaced, it can seriously limit your AC's cooling power.
Experts recommend using caution in temperatures above 90 F (or 84 F with 70 percent humidity).
When you activate dry mode, the fan on your AC is set to a higher speed, which helps circulate and draw moisture out of the air. Dry mode is especially useful during humid seasons such as summertime, when you may find yourself fighting against high levels of humidity in your home.
Cooling a house from 80 to 72 degrees is a common goal for many, especially during the peak of summer. On average, this process takes roughly two and a half to three and a half hours.
The ideal temperature for your AC depends on several factors. In general, it's recommended to keep your thermostat between 24°C (75°F) and 26°C (78°F) for a good balance between comfort and energy efficiency. Setting your AC lower won't cool the room much more but will make it run harder and cost you more money.
Research shows sleep can be disrupted by temperatures anywhere below 65 degrees Fahrenheit or above 75 degrees Fahrenheit. But for most people, heat interferes with sleep more than cold does.
It's advisable to keep your home below 80 degrees throughout the summer. A house that's too warm can be dangerous to people, pets, and the soft surfaces in your home. Set the winter temperature to 68 degrees when you're awake and 62 degrees when you're sleeping.
If it's 90 degrees outside, most people would set their AC to a perfectly comfortable temperature of 68-72°F.
According to ENERGY STAR, a division of the U.S. Environmental Protection Agency, 78 degrees Fahrenheit is the most cost-effective AC setting during the summer months. 1 And that's just the recommendation for when you're at home.
The average temperature that can help you save money is anywhere from 70 to 80 degrees Fahrenheit, giving your house just enough cooling to keep the hottest temperatures outside at bay.
While ENERGY STAR suggests 82 degrees, that may be too uncomfortable for most families. Most people sleep better when their sleeping area is chilly, so that's why the National Sleep Foundation advises 60–67 degrees.