When do you turn on your AC?

[Exterous]

My neighbor turns his on when its about 68 F(reedom) degrees outside. 77-78 is about when we usually turn it on although if its really humid that might go down to 75

 

[IronWing]

When I darn well please.



Assuming it's okay with my wife, of course.

 

[Malogeek]

Turned mine on last night for the first time of the year, it just hit 90 in our area and inside got to 80.

 

[dullard]

I turn it on as soon as I can not get the bedroom to 79°F or below at night. I try as long as I can to open the windows in the evening to have the bedroom cool for free. But, if the outside evening temperature is above about 76°F this just isn't possible.

I then turn it on for just an hour or so to get the bedroom to the desired temperature and then shut the AC off. This is because in the spring time, the high temperature can easily vary by 40°F in just one day. Sunday, Monday, and Tuesday the high was 91°F here. The high today is forecasted to be 55°F. So if I had the AC on Tuesday I'd pay to cool down the house and then today pay to heat it right back up. I'd rather just walk around Tuesday a little warm than to double pay like that.

 

[happy medium]

Turned mine on last night for the first time of the year, it just hit 90 in our area and inside got to 80.

Now is a good time, we must live in the same area.

 

[PottedMeat]

i can deal with no AC when i'm awake (90+). Full blast a bit before going to bed. if i can't sleep because it's too hot i'm worthless the next day

 

[Fardringle]

I turn it on when my house gets too warm to be comfortable. No specific temperature usually since "comfortable" tends to vary depending on the outside weather, and if it is me or my wife deciding what is comfortable..

 

[cbrunny]

Immediately after I finish with the Air Shampoo.

 

[AdamK47]

I have my thermostat set to 72 degrees while I'm at work, 68 degrees when I'm awake at home, and 63 degrees when I sleep at night.

 

[IronWing]

Immediately after I finish with the Air Shampoo.

That was Ironwing grade dumb material, I like it.

 

[Linflas]

I don't, the Ecobee3 does entirely dependent on the set temperature in the master bedroom and whatever needs to be run to reach that set temperature.

 

[lxskllr]

When it gets to 80F in the house. That takes awhile cause I have lots of tree cover. It'll probably be another month or two before it gets turned on.

Outside temp yesterday and today was 90F+. Still ~74F in the house :^)

 

[herm0016]

Still snowing here. The swamp cooler is still winterized, don't even have A.C.

 

[TeeJay1952]

6 AM Open House. All windows and doors open (with screens)
7 PM Dinner and close house. Air if 70.
11PM Air off unless it is 70 outside.

Michigan

 

[clamum]

Hmmm, probably when inside gets over 75 degrees F. Keeping the blinds/curtains closed during the day and opening the windows at night can really help to keep a house cool into the next day's afternoon, more or less.

 

[dullard]

Keeping the blinds/curtains closed during the day.

If you have horizontal blinds, then you want to close them the way that leaves the top part of the blind closest to the window (not the bottom portion of the blind). Otherwise you lose most of the benefit of closing them.

Let / be the blind and | be the window. Then you want this to keep the rising hot air from rising through the blind slats (hot air is trapped on the window side of the blinds):
/ |
/ |
/ |

Not this (rising hot air rises right through the blinds into the room):
\ |
\ |
\ |

In winter you need to reverse that direction so that any heat does rise into the room and the cold is blocked from sinking through the horizontal slats into the room (many people find this ugly though). Having the blinds open in daytime is better, but you don't always want to do that for privacy reasons.

For fun, one day I ran my exact horizontal blind dimensions through Ansys Fluent computational fluid dynamics simulations (http://www.ansys.com/Products/Fluids/ANSYS-Fluent). Having the blinds the wrong direction reduced the benefit of having blinds by almost half.

 

[JulesMaximus]

If it is 80 degrees inside I'll turn it on. If it is in the 70s I'm fine. We live near the coast so our house stays fairly cool during the summer. We really only run it during the months of July, August and a bit into September.

 

[ISAslot]

Try to keep house under 83 while i'm there.

 

[GagHalfrunt]

Last night for the first time. Hit 90* in the afternoon, so by evening the house was holding all that retained heat and was really uncomfortable. That's about standard, when the temps get upper 80s to 90s I turn on the AC, lower 80s I just open a window.

The people who turn theirs on at 68 probably keep the thermostat set at 74 in the winter.

 

[snoopy7548]

Will probably turn it on after I get home from work tonight. Second day in a row of >90F weather. I got home last night from work and the indoor temp only rose from 68F to 72F, then 74F after a few hours, and I think it was 76F when I woke up this morning (probably heat from the attic). The first floor of my home was feeling nice and cool but the second floor felt pretty stuffy. Maybe it's time for more insulation up there. My roof gets sun all day long.

 

[Capt Caveman]

Turned mine on last night for the first time of the year, it just hit 90 in our area and inside got to 80.

Turned on the first time this morning as it's the second day in row of 90 degree temps.

 

[soulcougher73]

When im uncomfortable

 

[AznAnarchy99]

74-75 is ideal for me. once it starts getting 78+ house gets too hot.

 

[KMFJD]

My neighbor turns his on when its about 68 F(reedom) degrees outside. 77-78 is about when we usually turn it on although if its really humid that might go down to 75

It used to be any time it got over 75f, now i rarely turn it on, used it a total of 3 nights in the 16 weeks i was in DR

 

[BurnItDwn]

I turn it on in the car when I am hot and opening the windows does not resolve the problem.
In the house, the womenfolks are weird and they like opening windows, so I usually turn the AC on when I get home from work and come to an EXTREMELY hot house ... sometimes even more than 80 degrees F.