I am going out of town for most of July. In the winter I would keep a minimum temp to prevent pipes freezing, but I can’t think of one good reason to worry about a maximum temp.
But in the interest of thoroughness, is there any reason not to turn off my AC for the month of July?
Don’t forget that air conditioning doesn’t just make the air cooler, it makes it drier. How’s humidity where you live?
The humidity factor won’t be as bad if there is not a lot of air exchange with the outdoors. If you run the A/C continuously before you leave, and your house does not exchange much air naturally, you should be OK for just a month. Longer than that, and it’s possible you could end up in a mold situation - especially if it’s humid/rainy outside. Really, IMO it’s going to be a coin-flip whether it works well for you. You could try just keeping the A/C set to a really high point, like 85-90, and get much of your cost savings that way. Or, you could buy a dehumidifier and make sure it has a drain pipe that can drain continuously to…somewhere.
That would be my solution. Look at a long-range forecast, see what the highest temperature is expected to be while you’re gone and set it to a few degrees below that.
Still - if someone were to decide this is a good course of action wouldn’t it be preferable to turn off the main breaker at the “fusebox”? That way, there is no power energized anywhere in the house proper except up to the main breaker box.
I don’t know about the OP, but most people keep some lights on when they leave town. If you throw the main breaker, you wouldn’t even have light from clocks (alarm, stove, microwave etc…) so the house would be really dark. Not only that, but if someone needs to get into the house (be it a relative you asked to go over and check on the humidity situation or a police officer/fire fighter if there was a problem) they wouldn’t have any light either.
BTW if you do plan do leave some lights on 24/7 while your gone. This is the time to get CFLs they’ll pay for themselves in the first month.
And unless the fridge and freezer are completely empty they will come back to a mess.
Obviously. I thought about mentioning that but considered that anyone doing this would have at least some foresight! Another angle would any burgler alarms systems.
I was looking at this with the angle of peace-of-mind because of fire. Coffee pots, VCRs, telephones, alarm clocks, everything is “on” and energised to some degree these days. It might make sense to turn off all the breakers to un-needed rooms and circuits, rather than the main breaker. Certainly, an electric water heater for example.
[anecdote]
While in FL, my AC broke and I didn’t have time to fix it for two months. The end result was green walls and a very expensive repair bill for what was a minor initial issue with it
[/anecdote]
Khadaji,
Having some family and friends in Pa. (one in Mechanicsburg) I can see no reason why you couldn’t turn the A/C off.Some of their houses don’t have it and I haven’t seen any evidence of detriment.(Comparing those who do against ones who don’t-the problem to my mind being the barrier between humid air and the first condensing surface).
It is possible that a programmable thermostat will lose settings if you kill the power.
This is PA, not FL. No reason he can’t leave the AC off. If he wants (and can) leave a window or two open in the kitchen.
Do you have a programmable thermostat? If so, have it fire up the AC for an hour. If you have time-of-day electrical tarriffs, run that hour at night to keep the cost down.
You can turn it up a bit beyond what you’d consider comfortable, likesay 80 degrees, but don’t turn it off altogether. You will have mold problems. Likewise with the fridge. You can turn it up just a bit because you won’t be constantly opening and closing it, but don’t turn it to a high temp.
Hey, Carson O’Genic , I passed through Mechanicsburg today on my way from West Virginia to New Jersey - weird!
I agree with you, having spent lots of time all over that/this/the other area. You definitely don’t need the AC on when you’re not there. I would recommend leaving the power on for the 'fridge and alarm clocks and such. Even though there’s it would make it easier for someone to break in, I’d suggest leaving some upstairs windows cracked open a bit for ventilation so the house doesn’t get super-stuffy (even 1st floor windows, if you’re comfortable with that - shouldn’t be a problem in any area of souther PA that I know of).
You live in PA? You’ve almost certainly got neighbors who don’t have AC. Ask them if their house gets invaded by mold in July. If not, you’re good to go.
I don’t know about mold elsewhere, but the fridge should be just fine if it’s emptied out, cleaned out completely (includes a rinse with bicarbonated water and a final one with water), unplugged and left with the doors slightly open.
My AC-owning relatives in both dry and humid places have the AC off 9 months a year - 6 months if you count the AC and heating as being one system (they aren’t always, over here). The worst case of mold I’ve heard of was blue cheese.
I think you’d be fine turning it off. I know I’ve lived in houses with no AC here and never had a mold problem. Our humidity generally runs 85-95% in the summer and I doubt yours is higher in PA.
Ignore them weird Floridians - you can’t even breath down there without a dehumidifier. 
Hey! Although that was one of the reasons I moved the heck outta there, I resent that 