promotion image of download ymail app

Raise AC temperature or turn off AC?

When I go to work and school I’m gone for 12+ hours. I usually turn off the AC and when I get home it’s around 83 Fahrenheit. I set it to 78 and by bedtime it’s that temperature.

Is this okay? My mother told me to just raise the temperature before I leave to 83 and then back to 78 when I get home.

Whichever way is more cost efficient for electricity?

7 Answers

  • #1 Your location is critical to answering this question.

    If you live in a very hot environment, you would be better off just turning it up a few degrees.

    This is due to system inefficiencies once the temperature load becomes too high for the unit to operate effectively.

    #2 Living in a temperate environment, turning the unit off would be much better in terms of energy conservation.

    Basically put, HVAC systems run longer to lower the temperature 1 degree the hotter the dwelling space temp.

    15+year HVAC Owner/Technician

    • Commenter avatarLog in to reply to the answers
  • 8 months ago

    they are roughly the same.

    • Commenter avatarLog in to reply to the answers
  • 8 months ago

    I'd stick with what you're doing now.

    If you turn the 'stat to 83 and the temperature gets any higher than 83 the A/C will be working while you're out and wasting power.

    Turn off the A/C when you go out and switch it on when you come home and you know for sure it isn't working while you're out.

    • Commenter avatarLog in to reply to the answers
  • 8 months ago

    In this case, as you have described, it wouldn't make any difference. The AC unit would do nothing (same as being off) until you lower the thermostat to 78 degrees.

    I would suggest that leaving the temperature set at 78, even while you are away would be a cost even scenario as the AC unit has to work very hard (thereby using maximum wattage) to lower the temperature to the 78 degree set point once you get home.

    If the thermostat is left at 78 degrees, the unit will only come on enough to maintain that temperature. The net working time, especially while no one is there to open doors, will be less than the hard work to lower the temp in the evening.

    • Commenter avatarLog in to reply to the answers
  • What do you think of the answers? You can sign in to give your opinion on the answer.
  • 8 months ago

    The A/C IS off as long as the thermostat is set above the actual temperature.

    That said my A/C has been set at 85° F since 2003 and turned off since 2015

    • Commenter avatarLog in to reply to the answers
  • Dale-E
    Lv 7
    8 months ago

    I think you are fine with turning it off. Tropical birds prefer it warmer. Depending on how you turn it off, you might be wearing out the on/off switch and have to buy a new thermostat. My thermostat has a little slider switch to turn it off. It is not going to endure being operated 520+ times a year for a lot of years. When it breaks down and fails on you, consider buying a programmable thermostat. But if you already have that set into a programmable thermostat, you are good to go and are already engineered for optimum.

    • Commenter avatarLog in to reply to the answers
  • Marko
    Lv 6
    8 months ago

    That's fine to do if it's working out for you. You can experiment with lower temperature settings to control the humidity that builds up when the system is off.

    • Commenter avatarLog in to reply to the answers
Still have questions? Get answers by asking now.