Should I set back the temperature when I leave my house?

If you get sticker shock each month when you see your energy bill, you may be looking for ways to save energy around the house. Here’s a common question our customers ask: “Should I set back the temperature when I leave my house?” After all, most people turn off lights and water when they aren’t using them. Why cool an empty house?

Air conditioning is one of the appliances that uses the most energy. According to the U.S. Energy Information Administration, air conditioning makes up 17% of the energy used in homes in mixed-dry climates like Los Angeles. So, it’s no surprise you might be thinking about your AC when you think about saving energy.

By the way, what is setback? Setback is a term used to describe the act of changing your thermostat from the normal, comfortable temperature set-point to another temperature in order to save money on HVAC operation. The setback temperature might not feel comfortable to you if you’re sitting in a space that is cooled to the setback temperature, but the idea is that you won’t be there while setback temperature is in operation!

Is it worth it to change your thermostat when you leave the house?

Before deciding whether or not to set back the temperature, there are a few things to consider.

First, think about how long you’ll be away. Will it be a few hours, or several days? Next, is how much to set back the temperature by. Setbacks are not created equally – setting back your thermostat by 1 or 2 degrees is different than setting it back by 5 or more degrees. Finally, is humidity a problem in your house? For LA customers closer to the coast, battling humidity in your home may be more of an obstacle than for those in the city.

Leaving the house for a couple of hours

It may be tempting to leave your AC running when you leave for work or head off to run errands. It’s one more thing to think about as you scramble to get out the door. Plus, it’s nice to come home to a nice, cool house.

But if you’re serious about saving energy, it’s important to adjust your thermostat while you’re away.

The Department of Energy indicates you can save as much as 10% a year on heating and cooling if you set back the temperature while you are away for 8 hours. Turning the temperature back 7°-10°F is your best bet. The ideal summertime temperature for setback is 78°F.

The truth is that you won’t get much benefit from setting back the temperature by only one or two degrees – but something is better than nothing. We always recommend our customers set back the temperature, even when they only leave for four hours.

If remembering to set back the temperature is a problem for you, consider investing in a programmable thermostat. When you use a programmable thermostat, you can set up your thermostat to set back automatically. And, you can start cooling your home before you arrive home by programming your thermostat to automatically turn on sooner.

When you’re away for several days

If you’ve read this far then you already know: it is absolutely beneficial to set back the temperature if you’ll be away from your home for several days. If your home is empty for weeks on end you may be tempted to turn off your AC completely.

But, there are a few more considerations when you’ll be gone for a long period of time. The most important consideration is humidity. Air conditioners help remove humidity from the air in your home. So, it’s important to keep your AC running even if the home is empty.

If you’re leaving for travel, set back your temperature setpoint by at least 10 degrees. But, don’t turn it off completely!

Another benefit to temperature set back

Setting back the temperature is an easy way to save energy. But, you’ll get even more bang from your buck when you turn up the temperature.

Because your air conditioner won’t be working so hard, you’ll be adding years of life to your AC system. When you run your AC at full-blast even when you’re not home, it is more likely to break down sooner. So, all the more reason to set back the temperature.