What is the most efficient way to use my home air conditioner?

Question

I live in a fairly large two story apartment (meaning my apartment is two stories, not that the building has two stories). I typically work from about noon until well after dark 5-6 days a week. Would it be more efficient to keep my a/c running 24/7 with the thermostat set to about 80. Or is it more efficient to turn on the a/c when I get home?

Right now I don't have a programmable thermostat that I could set to come on an hour or so before I get home.

Also, the lower level of my apartment gets pretty good shade virtually all day but the upstairs, where I sleep pretty much gets direct sun almost all day long.

Answer 1

You could try doing a test to see which is better. Since the outside temp may fluctuate, you may want to try testing of different days to get an good estimate. Anyway, leave the A/C off, curtains drawn. Once you come home, note the temp reading on the A/C. Then turn on the A/C and see how long it takes to achieve the desired temperature. (I assume you want the apartment to be cooler than 80 degrees). Then set your A/C on 80 degrees, curtain drawn, and allow it to run for the same number of days. Check the weather forecast and test with the A/C on during days with similar temp for fair comparison. Again, note the temp in your apartment when you come home. Figure any difference between days when it was off, versus days when the A/C was running on 80 degrees. In both cases turn on the A/C to see how long it takes to get to the temp setting you want to ultimately achieve. Depending on how long it takes to achieve the desired temp, you can figure which way is best.

good luck

Answer 2

It's better to keep it running all the time for cooling but heating is cheaper with a programmable.
Make sure the filter and outside part of the a/c (condenser)is kept clean so that it can exchange the heat easier.
To eliminate hot spots in your home set the thermostat with the fan in the on position to run all the time in the summer, and keep doors closed on the second floor as much as possible on hotter days. After the cooling season reset the thermostat fan setting to the auto position.

Answer 3

This is what I do: Hang drapes from your windows. Close them during the day and your cool temperature will be maintained.

On terribly hot days, I leave my AC on, BUT turn on a fan in front of it, and keep it spinning back and forth. When I come home, the house is several degrees cooler than outside, and the air has had a good chance to circulate around.

Install ceiling fans. When your AC is on, you leave them on too. You will only need a few hours of AC cooling, because those economical, humble fans do a great job spreading the cool air.