Fifth-floor prewar walk-up, two window units, no central air. I've been leaving the living room AC off from 8:30 to 6 because my ConEd bill was stupid last summer, but I come home to 88 and a sofa that feels like it's been slow-roasting all day. Then the unit runs full blast until after midnight.

Is the off-all-day thing actually saving me money, or am I just paying for one long recovery every night? Would a timer at 4:00 be the same or worse?

Off for sure. Get a smart plug or a heavy-duty timer, not the dollar store kind. I have mine kick on at 4:45, so by the time I get in a little before 6 it's bearable but the unit isn't fighting a 90-degree room from scratch.

Your problem is coming home and making the thing run nonstop. Pre-cool before you walk in.

Please please check the humidity before you just set it to off! I have a top-floor Inwood prewar and the real killer is the moisture. I put a little meter on the wall and it'll say 70% when it's 82 inside. Dry mode is so underrated for these old buildings! Have you tried running the living room unit on dry for an hour in the afternoon instead of full cool? It stops the sofa-from-hell feeling without the full blast.

Unpopular opinion but turning it all the way off can be a false savings. In an old brick top-floor apartment the walls, floors, and furniture hold a lot of heat. When you come home, the AC isn't just cooling the air back down; it's pulling heat out of everything else too. A unit cycling at 80 or 82 all afternoon might use less total electricity than a four-hour recovery blast at full tilt. I'm not saying keep the place at 70, but off is not automatically the cheapest setting.

Same setup, East Harlem, top floor. I did off for two summers and my place would be 91 at 6:30, then the AC would ice up trying to catch up. Timer set to 79 at 3:30 made a real difference, not just comfort. Bill didn't go up the way I expected. If your window gets direct afternoon sun, close the blinds before you leave too.

Blackout curtains or reflective film on your sunniest window. I face west and the living room bakes from 2 to 7. I leave the AC off during the day, but I also block the sun so the room isn't a pizza oven when I get home.

It's less about the AC schedule and more about not letting the heat in.

Appreciate the timer votes. I think my mistake is off plus no shading. The bedroom window faces south and the blinds are those cheap metal ones that just bounce heat around. Might try the film or at least decent curtains before I spend another summer fighting the recovery.

@EastHarlem_E, do you run a fan when the AC kicks on at 3:30 or is the unit enough?

Check your ConEd bill for an ESCO charge before you obsess over AC cycles. My first year here I was paying way over the normal supply rate because a door-to-door guy signed me up at a table outside Key Food. Cancelling that saved me more than any thermostat schedule.

That said, timer at 5 and fan is the way in my place.

Yes! Reflective film changed my south-facing room so much. I used heat-control film and it looks fine if you take your time with the spray bottle. Have you tried a window fan in the bedroom after sunset? I put one blowing out on the west side and it pulls air through from the stairwell side. On a night below 75 that's free cooling while the AC rests.

One caution about the smart plug route: make sure it's actually rated for an AC. A lot of cheap plugs are rated for lamps, not a 115-volt compressor kicking on. A heavy-duty appliance timer or a plug rated for 15 amps is the safer move. Also, if the filter or coils are never cleaned, your timer and film won't matter because the unit will struggle regardless.

Yeah, clean the filter and have someone hose the back of the unit. Last summer mine was blowing slightly warm, and I thought it was just too hot out. Turned out the coils were caked in dust from the air shaft. The super blasted it with water, and it went back to freezing. Free fix before you buy curtains, film, plugs, all that.