AC temp up when out?
 

Hello, I have been turning my AC up 2º when we leave the house for a little bit. Our thermostat will automatically lower the temperature back to the original setting after 2 hours. If we are going away for more than 4 hours, I will bump up the temperature and put the ac on hold.
A friend has said I am using more electricity by bumping up the temperature because it will take more energy to bring the temperature back down. I just don't know if that is true or not. I have picked up this habit from our days up north when we would turn down the heat when we left.
Any thoughts or facts would be greatly appreciated.

I have no facts to back this up, but I’m with your friend. The AC works hard to bring the temperature back down. Plus I don’t like walking into a too-warm house. :)

I just heard this dicussed on a radio talk show last week. The person who was the subject matter expert said to leave the thermostat at a constant setting unless you are going to be gone for multiple days.

Your friend is wrong. The amount of electricity you use is determined by the total run time for the AC unit. So, increasing the temperature setting for a few hours will reduce the run time and save money on electricity. You may want to consider buying a smart thermometer, like Nest, which is supposed to monitor your activities and automatically adjust the temperture settings to save electricity. I just leave my thermostat at the same setting all the time.

Even if your second sentence is true, that doesn’t automatically make the friend wrong.

I have read articles on energy conservation that it is cheaper to leave the thermostat at the same temperature all the time.

When we lived in NJ our power company offered free audits and suggested ways to reduce your bill. Number 1 was set it and forget it. We leave the AC at 74 24 by 7.

Here is a quote from the Department of Energy (energy.gov) about saving electricity.

"In the summer, you can follow the same strategy with central air conditioning by keeping your house warmer than normal when you are away, and setting the thermostat to 78°F (26°C) only when you are at home and need cooling."

Your AC unit will basically use a constant amount of electricity when it is running. It cycles on and off to maintain the thermostat setting. So, if you increase the thermostat setting when you leave the house, the unit will not cycle on and off as much and you will reduce the run time. Yes, when you return and reduce the temperature setting, it will take a few minutes to bring the temperature back down, but the overall effect will be to reduce run time and electricity usage.

I agree, homes here are relatively leaky, including heat ducts in the attic, so you spend energy cooling outside air intrusion.

New homes use the Ecobee, you can add sensors that detect when you are away (same with Nest) and raise the temperature automatically when gone a couple of hours. You can use an app to adjust the temperature down before returning home.

Other thermostats use the GPS in your phone to automatically set and reset temperature when away.

Added advantage cooling from a higher temperatures is a longer cycle will remove more humidity.

Ah, another case where the experts don't agree! :icon_wink:

Just anecdotally, I used to fiddle with my thermostat, turning it down when I left the house and at night. I stopped doing that last spring and my electric bills have stayed pretty much the same.

Depends on how low you set it. Anything below 72 going to burn electricity. I know this cause my neighbor sets his at 69 and the A/C Is constantly on. Where mine set at 77 and runs 1/2 or more His his does. I can’t set mine below 74 due to my lungs congest.

Most of the AC units in The Villages are single stage units. They are either on or off, and when they are on, they are using a fixed amount of electricity per minute. When they are off, they use no electricity. The lower you set the temperature, the longer the unit will run, and the more electricity you will use. It is as simple as that.

73 OR 74 Degrees year-round. On a budget plan with Duke. It went down again last year to $147 a month.

Comfort #1 priority. There is no big difference with adjusting constantly.

When we go away for more than a day we put it on 80 Degrees.

How much can you save? Can't imagine it's significant since cost of the electricity here is cheap.

You are correct that the saving is not significant. I keep my thermostat set at 77 degrees all year round. My electric bill averages about 85 dollars per month. Although, a smart thermostat like Nest would save you a few dollars.