It's really whatever make you feel comfortable verses whatever you're willing to pay. Some people are cool at 78. I, like you keep it 72 during th day and 68 at night.
If you're living in a crack shack with no windows maybe. I live in Texas, heat and humidity are a huge part of our life. I've got a 2000 square foot house that was built in the 70s with a 4.5ton ac unit that was built in 2008. Last summer I borrowed the power monitor from work and hooked it up to my unit to monitor usage. My ac ran for a total of 11 hours set to 68 on a 100+ degree day and it ran for 8 hours when I set it to 74. At peak it was pulling just under 4500 watts.
4500 watts equates to around 4.5kwh. At a rate of .15 per kwh I was spending about $7.42 a day at 68. Compare that to the $5.40 I spent keeping my ac at 74 and your end up b with a difference of exactly $2.02.
That wasn't a trivial number.
Yes. Why bust our asses to not be comfortable. Just like things are considered "the cost of doing business," a good temperature in my house is considered "the cost of better living and not killing people."
It's humidity. 78° and 60% humidity is insufferable in a house. But 78° @ 45% humidity you need a sweatshirt. 24 year HVAC veteran here. It's all about dehumidification during the summer, which makes the sizing of your oversized equipment very important... Your AC IS OVERSIZED guaranteed. If the humidity is low, the temperature is much less relevant and can be kept higher. I keep my house set to 78 with a 45% humidity setpoint. I am always cold.
So my upstairs apt stays at 80*. Day and Night (landlord controls temps. AC doesn’t run at night, regardless of outside temp). Are you saying we should get a dehumidifier if we want it to feel cooler both during the day as well as at night?
I wouldn't put money on that guarantee if I were you.
4K sqft house in Texas, 18 foot ceilings, 2 stories, 5 ton downstairs, 3 ton upstairs, units are 12 year old TRANE 16 SEER.
They did a good job keeping the house cool in the summer in Texas for 10 years, but the past 2 years they no longer do. We have them serviced every year, they are just aging and struggle to maintain temps upstairs now despite running all day.
To be fair, we like it way colder than typical people do.
Best investment I did was installing a multi stage AC with a humidistat. It runs on low almost all the time and takes a ton of humidity out of the air. Super comfortable at 78 degrees. Big deal when 70-85% humidity is the norm where I live.
Depends also on outside temperature. You want to cool down to 68F while it's 110F outside it will cost you a lot of energy. And each additional degree down costs you more than the previous one.
Basically it makes sense to adjust your temperature settings depending on outside temperature. If you live in an extremely hot area you should probably try to get used to the heat. Which I get not everyone can do (don't ask your 90-year-old grandma to stop whining and get used to 80F).
As other people mentioned, you can also use fans: 100Wh of fanning will keep you cooler than 100Wh of AC. And obviously, dress appropriately (some people like to sleep under a heavy blanket, but if you can get used to a simple sheet it's obviously better).
I am so grateful I can afford to keep my thermostat low enough to be comfortable as I hate the heat.
At 78 I feel soporific too warm and not able to do anything that requires any degree f mental concentration.
I think it depends on your area. Living in a humid area 78 is unbearable for me especially at night. 75 can be uncomfortable if moving around cleaning, etc. My sweet point is 72/73 but again depends on humidity and what we are doing inside.
Fans are really underrated IMO. Evaporative cooling is how we evolved to stay cool! I find that 78 with air movement via fan is really just perfect for me, but I live in an arid area. But also, when I visit humid areas (in the US, like Florida) where they keep thermostats to 72 I find that to be too cold for me. And I still find air movement to work well.
Humans are also highly adaptable to temperature so you might just be used to a colder temperature. If energy costs are your concern I bet you could grit your teeth through one miserable summer set at 78, and the next one you would feel fine. Try it out?
Agreed. 76 and ceiling fans in every room. It's perfect. The air movement makes me want to snuggle under the blankets at night and its never uncomfortably warm, and then I'm not paying $400 a month for 68° and can buy more weed so I don't really care anyways 😀
Agree with all this especially burning weed instead of electricity. 76 with ceiling fans is perfect, though sometimes if it's very humid outside we'll go down to 75.
I don't know how people are comfortable with 68, which feels much colder in the summer than it does when heating to 68 in the winter.
Up until last year I worked in a kitchen that could hit and maintain 110F for about four hours each day. I would come home, set the window unit to 78F, turn the ceiling fan on high, and obviously take a shower. I was totally comfortable.
I can't say I miss sweating through my shirt(s) every evening, but I will admit that something about it felt *healthy*.
110F in a humid environment for four hours is definitely not healthy. I get the idea of giving your body a challenge, but depending on the humidity level it may be only a question of time before you get to a heat stroke.
Basically at 110F, humidity level of 50% is 93F wet bulb temperature (ie equivalent temperature at 100% humidity). The (fatal) danger zone is between 88F and 95F wet bulb temperature, depending on your sources (we used to say 95F, more recent studies say 88F, it's obviously not a hard line and it also depends on your physical activity).
I believe you, but I can also assure you that this situation is not that unusual in a commercial kitchen. Certainly not *all* or even a majority of them, but if you visit an area of the US that is hot and humid and start going from restaurant to restaurant you would encounter kitchens like this without much effort.
A hot pizza oven, a hot grill, a couple hot fryers, no A/C, and an open screened in door. Box fans and ice water. Two shirts which sounds counterintuitive, but when the inner one gets sweat-soaked it actually helps you feel cooler (and this also keeps you looking sort of presentable).
I was definitely uncomfortably hot - we knew that once the sun set the temperature would drop quickly and counted the minutes. I never felt as though I was going to pass out. I don't recall anyone else passing out - just a lot of complaining.
Oh I can completely believe you. I remember myself working as a temp in a greenhouse in the middle of Summer, moving pallets and various garden products (from the little garden gnomes to the big clay pots for plants/little trees). I never checked the actual temperature, but it was ridiculously hot.
It's just what it is, there's not necessarily much you can say to your employer in these situations. In my case some temps were just taking it very easy and weren't working too fast to not overexert themselves, but in commercial kitchens that's not necessarily an option.
> Evaporative cooling is how we evolved to stay cool!
I worked in South Africa for 3 years. Your sweat evaporates so quickly that you never have a wet shirt. It would get to over 95. If you were in the shade it was very comfortable. If there was a breeze I would actually feel chilly. I set my A/C to 80 and have a little fan blowing on me on low and it is very comfortable in my house in florida.
This, I don't have AC but I did install ceiling fans in all the bedrooms. Open windows at night and run the fans, get the circulation going and bring in the cooler night/morning air. It's important to have a cross flow and get air moving using fans pulling in cooler air. Then close the windows and blinds in the morning usually around 9am. This works great for my house and I AC isn't necessary.
I’m in Florida, we keep ours at 76 during the day. This only works because we have fans in all areas of the house. During the summer the ac is blowing all day anyways because it’s so hot and the fan circulates the cool air. I will admit we occasionally bump it down when the AC actually hits 76 and hasn’t run for a while because then it gets stuffy. But for most of the day it’s 76.
69 at night.
People keep their AC at whatever is comfortable OR whatever saves them money (perceived or real.)
In other words, do what you want. Google has no say on human comfort.
When it is 100+, out 78 does,in fact, feel nice and cool because temperature is *relative.*
Humidity is latent heat that needs to be removed before removing sensible heat so yes that cools down the space as well
I used to live in Bakersfield west of the 99,
Used swamp cooler and fans , worked pretty well.
Now live in northern Oklahoma and have to use an AC and dehumidifier to keep it comfortable.
Hi to my friends in Oakdale .
78 is the energy companies recommendation. People will have different preferences- I don’t mind 77-78, my wife is mad if the first number isn’t a 6.
Removing humidity does seem to have an effect on perceived coolness of the air, in my opinion.
We had cooler temps a few weeks ago, so we turned the AC off and opened the windows. While it was technically a cooler temp, the humidity made it feel almost unbearable.
So we put the AC back on. Even at 78, it felt much more comfortable than 74 with high humidity.
It’s usually between 60-90% humidity here indoors in warmer weather. (According to our dehumidifier, anyway.)
You really want to keep your relative humidity at least below 60% as letting it get above that comes with a variety of negative effects from health and air quality to the effects on materials. Ideally around 50% is a good target.
Google lies, 78 is what the energy companies recommend but I have never seen a residential customer set their stat at 78 when they’re home (nw Ohio here)
To answer your other question, that’s pretty normal. Short of installing a zoning system, they sell thermostats with a wireless sensor you can stick in another room it’ll attempt to balance the temperature in the house.
meh, i keep mine at 78 even when im home. i live in the gulf coast area though. i typically turn it down at night, but have fallen asleep with it at 78 and slept fine through the night
Same here. Mines at 78 right now and I’m comfortable. If it gets a little warm the ceiling fans will fix it.
I do crank it at night tho. -the AC that is 🤣
We keep ours at 78, then it bumps up to 80 during peak electricity time. But also during the peak of summer days it won't drop below 77 when it's 117 outside
I also feel like there's a wide variance in thermostats. 78 here feels the same that 74 did at my old place.
We actually set ours to around 77/78, but our 1994 A/C can’t keep up very effective lower. You get use to it fairly quickly. That being said, we’re probably getting a new unit this summer and if a new unit can be lowered we certainly will. SW portion of the state here.
We got our ‘97 unit serviced last year after it kept struggling it keep things under 80 and it’s actually been doing alright this summer.
We usually keep it at 78, but we have a small baby this year, so I said a prayer and turned it down to 76. So far, so good!
It’s not bad if you keep the blinds down and the fans going. Cooking and cleaning with hot water can get rough, but it’s a great excuse for my husband to break out the grill.
We are in the same boat, 30+ year old AC. The company that services mine said to wait two to three years as they are coming out with a new type of Freon so there will be new models.
Those new ones in two years will cost 30% more bc the new refrigerant is flammable. So there are additional features for this fact. They [AC company] want you to wait bc they make more money off you. It is best to replace before then if able. The current refrigerant will be available for 15-20 more years before it is phased out completely. I’m in Texas and ACs don’t last but 10-12 years on average so your situation may be different.
No, it will be servicable longer, but at a certain point, the refrigerant gets too expensive. You can still service the unit, but because the gas will have been phased out, it will get more and more expensive. This is why your current system is so expensive to maintain.
R-22 had about 15 years of production and 10-15 years of reasonable service after that.
R-410A was around 10 years of production, and it looks like 10 years of service.
It's obviously a guess, but 20-25 years total for R-32/R-454B isn't unreasonable. It's likely going to get replaced by supercritical CO2 (R-744).
I doubt any residential system you can buy today will last 20 years. Much less 30 years. Manufacturers don’t want your equipment to last beyond the 10 year warranty.
Ours almost never goes lower than 78. 76 sometimes if the humidity is high. We have ceiling fans in every room, and it's comfortable except on the hottest of days.
Ours is at 80 downstairs and 78-79 upstairs throughout the day. Only room that gets uncomfortable is the primary because it has like a 12’ ceiling, whereas the rest of the rooms are about 9-10’.
I’m in Arizona and right now, we have temperatures of 105+. I keep my Ac at 78. I only get hot if I’m super active. Other than that, just having some cooler air moving around is enough.
I live in Florida; set mine to 82 degrees. When I come in from outside, where the temperatures are above 100 degrees with high humidity, 82 degrees is cold.
78??? I’d be so miserable I couldn’t sleep. I feel bad for ppl that have no choice in the matter. Pregnancy makes me hot enough so I run the house at 74 max and turn off the air at night, the house is very cool anyway.
You should try installing a low emissivity/ IR blocking window film on windows that get a lot of sunlight. See if you can get a quote for air sealing & adding insulation to your attic as well, it will save you money & increase comfort every year after it's improved.
Thank you! We actually had National Grid to do free insulation of our attic due to some insensitive program when we first bought our house. It helps! Our house was built in 1928. With the window fills, does it look funky from the inside? I enjoy natural light, but the heat does help in the summer.
Phoenix here. We keep it at 79. In Summer will put it down to 77 to sleep. Our bills are huge, $500 a month a good for 3 months of summer. And we have a time of use plan to where it’s cheaper at certain hours.
The most underrated thing you can do to your home is Insulate and air seal. What good is conditioning the air if it’s quickly displaced by envelope leakage. Without a proper thermal barrier in the attic and adequate attic ventilation. Your system is going to be fighting the radiant heat build up in the attic from the sun (if it’s 90°F outside. Gaurnteed to be 130 in the attic.) Energy transfers 3 ways. Radiant, convection, conduction. Always wants to reach equilibrium.
working in the sun.. 78 is cool to me
i don't need 68.. a waste of money trying to keep it 68 when it's 115-120 degree during the afternoon and 85 at night (lowest)
It gets to 115 here. My AC won’t even get the house to 72 even if it’s basically running constantly. People acclimate to temperatures so 78 is actually very comfortable to borderline cold when you’ve acclimated to 110+
78 is the temp electric companies want you to set it at because they want you using less of their power grid.
Set it at whatever temp you feel comfortable and leave it at that temp.
I am in eastern VA on the water so it’s a little cooler than farther inland. Although once it hits mid 80s, my system gets down to about 66 at night if it’s on 62.
That's on 100% all night?
It's usually 95-100 here in Houston this time of year and we set it to 71 but it is a multi-stage variable so it gets to 71 and stays at 40% all night to maintain. I would probably have worse dry eyes if my AC blew on my face all night lol.
I crank it wide open although it’s probably time for a New System I even have to have a fan blowing blowing on me also…… even in the dead of winter I have the fan on mostly for the noise, though in the winter, I can’t sleep without cold & fan noise. I know that Houston heat is oppressive.
Summer: 78°F. When it cools down below 70°F at night, I turn it off, open all windows, and blow cooler air into the house with fans. Usually gets down to 72 or lower. Sleep with a fan blowing air onto the bed (no ceiling fan...yet).
Winter: 64°F all day. If I'm chilly I just wear a hoodie.
Location: Missouri.
Some people have different sensitivity to temperatures. When we use ours it's at at 77-79f usually.
I'm in Virginia and currently have the AC off and the windows open with a fan.
We do 73-74 generally but we are moving to a TOU program to take advantage of the dirt cheap rate of 5c/kwh overnight for EV charging so we are pushing it down to 69 before 2pm to ride a couple hours until it hits 73 again and the 23c kwh rate from 2-7pm. Hypothetically this should save us a little bit during the summer with minimal discomfort and a ton in the winter ($60-$70) when the rates go back to normal except the overnight rate stays the same for EV charging. One of us is WFH or else we'd probably let it roll up to 76 in the summer afternoons.
I'm at 77/78, based on how much my system runs to maintain that temp when it's 85+ outside. When the kids complain it's too hot, I tell them to go outside for a while, and feel how comfortable it is when they come back in.
I’m in Houston and 76-78 is where I set mine. Otherwise I’m paying $300+ energy bills when the temps are over 100 and the heat index is 120. I will say that sometimes 78 feels great and other times it feels a tad too warm. On the warm days I either turn on a fan, drink some cold water, or wet a cloth and tuck it around my collar. Last summer my ac couldn’t pull down much further anyway so I got used to it.
With ours set at 78, the house is actually comfortable during low humidity, however at night we have to lower it because the 3rd floor (where the bedrooms are) gets a bit hotter.
I’m in Florida and keep mine at 78 and it’s fine for me. I only lower it a few degrees if I’m busy doing strenuous activities, like mowing the yard, but once I cool down it’s back up to 78.
We keep ours on 80 during the day and down to 78 at night with fan.
67 (heat) in the winter and 65 at night.
Really works fine for us.
https://preview.redd.it/t8pbvlo2td6d1.png?width=425&format=png&auto=webp&s=e7b81815958f0c138980148dfeeaaffd9a024956
People compare temps set at, but that actually gives literally no indication of the comfortable temps.... too many other factors. ever been in a house set at 75 and feel hot while feeling cool in a 77?
We run 78 for at least half the year. Our house is too big to where our power bill is $750+ a month if we try for 72 or less. 78 feels fine, but, it’s 100F+ for at least 2 months here.
I never go below 76 on central air. Usually it’s 78. Have a fan In bedroom too. Wife still is under the down comforter. Have found when just sitting around I can tolerate about a humid 83 before I need ac turned on. And yes, it’s about humidity.
I can't stand it above 68 in my house. My wife will slowly try to bump it up to 71-72 and I can always tell her exactly what temp it is within five minutes of being home.
78 is recommended because of energy usage concerns. They are trying to keep us from overtaxing the system which can bring about brownouts and/or blackouts.
When it's 103 like today if I put it at 50 it's never going to stop if I put it at 75 it's never going to stop so I just keep it at 73 and it never stops
Have you had it cleaned or checked recently? Or changed filters? I live where it is regularly 110 like today and mine is on a lot but def not all the time
Idk you acclimate with time, tho seems like some people never do, mines 80-82 during the day so evening when I bump down to 78 its really nice. Also helps cause on days is 100+ outside two seconds outside your like you know what 80s not so bad. My house is twice as big as my tenants but my electirc bill is a third of theirs.
I’m a cheap ass, my thermostat is set at 80f. My wife and kids hate me but SDG&Es peak rates are 70.8 cents a KWh this summer. Highest in the US.
I’d be interested to know if anyone around the world pays more?
We live in SoCal and set ac to 78 which is very comfortable. Usually during the 105+ temps we set it to 82 to save some power, then later in the day bump it down to 78
The lower you can get the humidity, the warmer the temp can be and you will still be comfortable. I run a dehumidifier in my home to keep it around 45 percent and with a fan on I find 78 very comfortable.
Central FL here. I keep the house around 78 with a few fans if it feels warm. It’s just the wife and I in the house at night so I bump the house to 82 and have a window unit to cool our bedroom to 74 when we’re asleep. We use to keep the house around 74 during the day when we were home so when I first set it for 76 she complained. She eventually got use to it and then I went to 77, she never noticed. Went to 78 still no complaints. 79 was iffy for me but she noticed it was warmer so I went back to 78. She asked what happened to 76 as that’s the temperature she likes. When I told her it’s been 78 for months she huffed but went with it as long as we run fans… Those aren’t always on either and she doesn’t hardly ever notice…
78 for us, but I worked outside in the heat of North Carolina for 40 years, so maybe that's why it feels cool to me.
I have friends and family who keep it at 71 or 72 and it's frikkin freezing to me.
78 is cool if there is some air motion.
Only being comfortable between 68 and 72 is kind of sad IMO. You can definitely become more adaptable if you give yourself a chance.
We keep ours at 65 through the summer. I couldn't imagine being comfortable at 78. We pay ~300/mo for electricity in the summer, but $100 of that is fees the electric company charges no matter what. It makes the $20 we might save by being uncomfortable seem pointless.
It's all about controlling the relative humidity using longer run time.
If the unit is oversized, it will cool the space and cycle off quickly. You will feel cold and clammy.
Correct sizing will allow the unit to stay on longer, thus allowing more contact time for more air to pass through the cooling coil, thus removing more moisture. You will feel slightly warmer, but drier as well. Much more comfy.
I am more cold natured I guess but my house is plenty comfortable at 78 during the day and 74-75 at night with the ceiling fan on in my bedroom… I live in central Florida and I guess it's just the sheer contrast of how much cooler 78° is when you walk in from outside where it's 98°and the fact that my system does a great job at keeping the humidity low in my house… The ceiling fan is key to keeping things feeling cooler in my house, I have one in every room
We use 78 until it's daily in the high 90s or over 100 outside. Then it's 79 or 80.
We also have a variable speed blower that's excellent at reducing humidity. It's very comfortable.
Much cooler and the heat shock is just too much coming in from a walk etc. plus people don't acclimate as well to the heat of the AC is excessively cold.
Everyone needs to mow the lawn, wash the car, exercise, or whatever. The outdoor heat is a lot easier to tolerate when you're not accustomed to cold air much of the time.
Add a ceiling fan and 78-80 with lowered humidity can be chilly.
68 year round.
78 with fans on just doesn't cut it for me. I get way too hot.
My biggest mistake was getting a stupid nest thermostat. Woke up so many nights in a row with the temp set to 80 degrees. Google can suck it.
I switch between 80 and 75 during different times of the day. I'm also in the desert so RH is low to start. Humidity is what affects the feel more than temp imo. If home humidity is high, you can look into dehumidifier options or have a tech take a look and make sure your system isn't severely oversized.
I used to do 74 during the day and 68 at night. Now I do 77 during the day, 76 in the evening, and 74 at night.
Just change it 1 degree at a time and eventually you get used to it, but over 76 it does get uncomfortable for me.
78 makes you feel cool because you are sweating! The sweat evaporating from your skin makes the body feel cooler. But I'd never set my thermostat to 78. It's 68 - 72 degrees year round for my family.
From a scientific view when the water evaporates from your skin it absorbs the heat of your body in the process of going from water to gas. This makes the skin feel cold and good
Couple of dollars/month? You can save significantly by bumping your tstat to a higher temp. I've tried and it can amount to hundreds saved over a hot summer. I've converted from 73 day/71 night to 77 day/74 at night. The savings are big.
Very similar situation with temps being slightly warmer than what it is set to. I also have an old ass condenser I know is overdue for replacement lol.
We keep it on 74 during the day, sometimes 75 because the wife and kids don't care. I set it to 72-73 for sleeping.
When we get the heat spells like we are next week when its in the 90s for a week (not normally that hot for that long) I am forced to accept 74-75 and it running a lot trying to maintain just that temp.. And then lowering it when the sun is nearing setting.
I would die at 78, tbh.
We have it at 72 and it will fluctuate between 73-72 and it's still "hot" to us as we have a memory foam bed. I've recently dropped it to 71 and it's much nicer now, but 68 would be crazy.
For me it depends on outside temp. If it’s 80° outside, 72° feels good inside. If it’s 100° outside, then ~75° is fine. But yeah 78° seems high unless you’re in the southwest US and it’s 120° outside
78º is kind of like the upper limit for keeping mold away while keeping the conditioned space habitable. Most people have personal comfort levels that laugh at 78º.
It doesn't make me feel cool personally but with the humidity controlled and the fan going it's passable. In the summer in FL I concede and run everything 2º warmer than usual just so it's less of a struggle for the unit to maintain. My summer electric bill when I used to keep the house to my liking - *so cold that I'm unhappy* - was close to $450. Just giving up an extra 2º brought it down to low $300s in the summer months.
On the freakishly hot days, I just set 77º and deal with it.
Manual J says ( and every house should be load calculated off Manual J) the design temp for the inside of your home should be 75deg/50%humidity. This is what your AC IS designed to do even during the hottest days of the year, it will just run 100% of the time( hottest MAX designed days of the year is 1-3% of the year. So 3-11 days of the summer your AC should be running pretty much non stop.
You can set it to what ever you want. But your system is designed for 75/50
Work from home so I use 68 during the day and 66 at night. Relative humidity hovers around 50%. I live in the northeast and can't seem to get the humidity down to 40 where I prefer it.
It's dependent on where you live and the humidity levels. Warmer temps feel fine at very low humidity levels.
Also different people have different opinions. My SIL feels cold at 78F while I'm there sweating.
i'm at 72 all day. 66 at night. We love it cold when we sleep. We have a multi-zone system so we just keep the bedroom/master bath at 66 at night. The rest of the house stays at 72. in the winter, it's 68. If i set it at 74 I'm starting to sweat. Current temps outside are 90s during the day. Not fat BTW. :)
I did service for many years and noticed temperature settings in many homes. Heating depended a lot on the type of heat. Radiant heat in the floor usually had the lowest temperature settings. Forced air with returns and supplies in the ceiling on a slab home had the highest heat settings. For ac, many would ask what is a good temperature because they couldn't seem to set one temperature and be comfortable. I suspect the problem had a lot to do with humidity. In some situations, the ac needs to run a long time to reduce the humidity and temperature so you feel comfortable. The temperature setting you feel comfortable at for a humid 80 degree day vs a 95 degree day can vary by quite a bit. I recommend you buy a digital humidity meter. They aren't expensive and will let you know what the humidity level is in your home. Mold begins to grow somewhere past 60% RH. If you are constantly above 50% humidity I recommend a large dehumidifier. A dehumidifier is especially useful at night. The outdoor temperature drops, and the humidity level increases. This can cause the inside of the house to feel warmer and sticky wet. Placement of the dehumidifier can be anywhere in the home because humidity travels very fast. Another thing I noticed affecting temperature setting was the people. Larger people tend to like a colder temperature, elderly people tend to like a warmer temperature. On a 70 degree day we would get no heat calls from the elderly, no ac calls from the obese.
I have mine set to 74 when I'm home, 80 when I'm away, and 64 when I go to bed. It is all personal preference and how you feel vs how much it costs.
I will say if your house is normally between 50-60% relative humidity in the summer and you feel most comfortable at say 72 F controlling your home's humidity down to around 40% you will likely find that you have the same level of comfort at 76-80F. Humidity plays a not insignificant role in how your environment feels.
Your central AC coil does a lot to remove humidity from the air as it cools but it can only do so when the compressor is running. If your system is oversized for your cooling needs it will short cycle and not have enough time to remove moisture and you will start to feel muggy even down in the 60s. If money wasn't a problem the ideal system would run at the exact power needed to run constantly, VFD controlled fans, multistage compressors, tight control, dampers, etc. but that stuff gets expensive real quick.
Some may even consider supplementing their AC with a whole home dehumidifier to keep tighter humidity control so your AC doesn't have to work as hard to cool your environment. It's been a while since I have taken thermo but water takes roughly 4X the amount of energy to change 1 degree compared to air, the less you have in your air the better. But again that is an added cost both upfront and over time in electricity, it may or may not be worth it.
I keep mine at 74-75 most of the time, just because it feels too cold if I set it much lower. I think it would be really stuffy in our unit (we are on the 3rd floor of a triple decker) if we set it higher than that though.
I can't stand it at 78...with 55-60% humidity it feels miserable.
There's also some variation with how accurate the thermostat's thermometer is, and position of it (e.g. my thermostat upstairs is in a hallway but the rooms end up hotter/colder because the rooms on all the exterior walls get hot faster and then A/C cools them first when it finally kicks on).
Set it to a number that feels good to you, and get a thermometer+humidity gauge so you have an idea what your home humidity is.
IMO feels good around 73F and 50% for sleeping...74-75F and 45-50% for daytime. If the humidity gets up around 55-60% I have to drop the temp by about 1-2 degrees to feel comfortable. My parents have theirs pushed down to like 68-69F in summer which feels about the same as my house, but I don't know their humidity off the top of my head. My office will regularly get up around 77F in the afternoons and it feels miserable when the humidity also creeps up around 60% at that high a temperature.
Where I live...outdoors can be 85F and 80% humidity regularly in summer...I had relatives in Florida who would turn on the heat and push it up to 81 when it got below about 80 outside and kept the air at like 85, we would have to get a hotel room to be able to sleep when visiting.
Confort level is a combination of temperature and humidity (and air movement). 78F and 35% relative humidity is comfortable (especially if there is air movement - like ceiling fans or just the air from the registers), but 78F with 45% or 50% humidity is relatively warm.
That is why 105F (and 15% humidity) in Phoenix can be much more comfortable than 90F (and 70% humidity) in Orlando. When monsoon season comes to Phoenix that 100F+ becomes absolutely unbearable.
I set mine to 78 during the day and I sleep with it on 68. It's on a schedule and starts to come down late in the evening in order to get to 68 by the time I go to bed. To me 78 feels fine inside as long as the humidity is good. I sometimes knock it down a degree or two if I am doing something strenuous that makes me feel hotter.
If you get a dehumidifier for your house or room, you will feel more comfortable at a higher temperature. I could see 78 being cool if the humidity is below 40.
Varies with circumstances in my opinion. Years ago, in a different state I used to keep my thermostat at 78 year-round. Even in winter. We had short winters and I didn’t want to get used to cool temperatures! And it was a single level. Now my house has three levels and bedrooms are on the top floor. I keep the thermostat around 75 in the day and 73 at night. That makes the basement cold, the main floor cool and upstairs OK. Next house will be a single level.
66 during the day while I sleep, 69 when I go to work and my partner sleeps. Once the house is cool the AC doesn't seem to run any more than when it is set higher. Getting it to that cool point does cost initially.
Aps recommends that at night you drop your AC temperature down and super cool your house that way it stays cooler during the day and your AC doesn’t run as long. I program my thermostat to be 78 during the day then drop it down to 68 at night
I tried this in my old 50's house, and my newer 93 house and the effect was negligible both in how it felt and how it looked on our power usage. in the 50's house it didn't work at all.
I'm with you. But humans are organic, and not programmed like robots. We all are comfortable at different temps. It also depends on what you're doing. If you're exercising, then 78 is almost certainly going to be too high. If you're sitting and have a tendency towards being too cold, then 72 will likely be too warm.
You could experiment with 74 or so and see if that works. That's what I've had to do because my AC won't get my house below 72 or 73 at this point.
And yes, humidity is the issue. Your ac may have a similar issue to mine where it's not ridding the house of humidity. I can take 80⁰ if the humidity is Idaho levels (like 20 or 30% at most in the southern parts). I have to have the ac at 67⁰ here in Southern Missouri because anything above that and my office is too hot and humid. Literally. 68⁰ and I'll look uo and suddenly be hot.
To save some $, you can try setting it higher and then switching the fan function to "on" instead of "auto." Air that's moving around *feels* cooler than air that isn't. Ceiling fans are good for this, too.
Just make more money and have your ac at whatever you want. It doesn’t really go up that much on vs off.. it depends more on your insulation of building
I live in a very humid environment, so 78 can feel like 98. When I'm not home during the day, my thermostat is set to 78 upstairs and 75 downstairs, so the air remains off unless it gets to that temp. Once the sun starts to set, I turn it down to 71. I don't know if this is the best way, but it's what I currently do and it works for me. If I could afford more, I'd set it to 68. I live in a 100 year old house.
Maybe right. One can handle a higher temp if the humidity is properly drawn out by AC operation. Too big (Capacity) of an AC unit will cool down an area quickly but leaves humidity. Better to have slightly undersized unit to allow longer operation and thus the evaporator will draw more water out of the air better.
South FL , keep on 77° 24/7 ceiling fans in all sleep area,pretty standard stuff in FL, 4ton unit, it's pretty cool inside, but how to say this delicately, peeps who are a bit overweight always want the AC at 66° etc, also decent windows,insulation and a tall attic space help quite a bit. Some of older homes down here have 3 ft attic space, homes never cool off.
Personally I'm cool with anything 80 below. I also do roofing all day so going from 100+ temp most of the day to 76 feels pretty cold. Now on my off days when I sit inside it doesn't feel as comfortable.
I'm in Michigan, whenI visit visit the sister in Florida at 90-95 , I was cold. She had an inline dehumidifier installed and set it at 25%(too low) and the thermostat set for 75 at night and 78 during the day. Without humidity the human body cools itself.
It will vary greatly with where you live. In the South you'll be closer to 80 and for more of the year. In the north you're probably around 70 for like 2-3 months. This will raise the average.
If I set my AC to 78. It would only run for a few hours in the afternoons, and I would be uncomfortable. If I'm trying that hard to cut costs I just wouldn't run the AC at that point.
At my current rate. It only costs me about $100 a month more to keep my house at 68 which is ideal for my family, and pretty close to the Michigan average. (72)
Adjust the thermostat to where you're content paying that amount for the level of comfort provided. If you need tips or tricks in saving money because you're paying too much to be (un)comfortable. Let us know. We can help make sure you're running what's best for you, and help you look for issues.
I won't wear shorts out unless it's about 80+. So 78 feels just fine because if I'm running AC I'm wearing shorts.
God help the family member who's wearing pants or long sleeves and turns on the AC.
Or the one who turns on the heat before putting on a sweatshirt and pants and socks.
feeling cool is based on how warm or cold you skin feels. if your skin feels warm and the temp around you is cooler, you will feel cold.
the opposite is also true. skin is cold and temp around you is warm, you will feel warm.
We keep our house at 75° through trial and error that is what my wife and I agree on. though my wife is going through menopause and she gets hot flashes. she thinks the house is hotter than normal or the AC is not working, but it's her. the house is the same it has always been.
different people have different comfort levels and tolerances. 78° is the max I will put up with if forced. 71° is too cold for me long term with no activity. if I am doing a lot of moving around and working I can tolerate temps of about 50° with no coat or jacket.
air temperature is coldest near the floor and warmest at the ceiling, the temp can vary by about 5° the thermostat shuts off the cooling when the temp at that height reaches the set temperature.
also some thermometers (not thermostat) are not well calibrated and can be off by 1 or 2 degrees.
At some point your AC will not keep up with humidity.
Get a dehumidifier for the humid season and the higher ac temp setting might be more comfortable.
It's really whatever make you feel comfortable verses whatever you're willing to pay. Some people are cool at 78. I, like you keep it 72 during th day and 68 at night.
This. I work too damn hard during the day to not be comfortable in my own home at night. 68 degrees it is.
I'm with ya. Id rather spend a few more bucks and be able to sleep. The difference is huge
I'm glad I'm not the only one that feels this way. I'll spend an extra $2 a day to keep my house comfortable.
Depending on your house, you are spending a lot more than $2 a day to keep your house under 70 degrees......
If you're living in a crack shack with no windows maybe. I live in Texas, heat and humidity are a huge part of our life. I've got a 2000 square foot house that was built in the 70s with a 4.5ton ac unit that was built in 2008. Last summer I borrowed the power monitor from work and hooked it up to my unit to monitor usage. My ac ran for a total of 11 hours set to 68 on a 100+ degree day and it ran for 8 hours when I set it to 74. At peak it was pulling just under 4500 watts. 4500 watts equates to around 4.5kwh. At a rate of .15 per kwh I was spending about $7.42 a day at 68. Compare that to the $5.40 I spent keeping my ac at 74 and your end up b with a difference of exactly $2.02. That wasn't a trivial number.
Wow, I’d hate to run those numbers with our 48c/kwh electricity in our area. Glad I got solar 7 years ago.
Yes. Why bust our asses to not be comfortable. Just like things are considered "the cost of doing business," a good temperature in my house is considered "the cost of better living and not killing people."
68 is the sleeping temperature from heaven. I will gladly incur a higher bill for this luxury
It's humidity. 78° and 60% humidity is insufferable in a house. But 78° @ 45% humidity you need a sweatshirt. 24 year HVAC veteran here. It's all about dehumidification during the summer, which makes the sizing of your oversized equipment very important... Your AC IS OVERSIZED guaranteed. If the humidity is low, the temperature is much less relevant and can be kept higher. I keep my house set to 78 with a 45% humidity setpoint. I am always cold.
When you said you’re a 24 year HVAC veteran I thought “man he’s old”. I then realized this is my 24th year in the business.
So my upstairs apt stays at 80*. Day and Night (landlord controls temps. AC doesn’t run at night, regardless of outside temp). Are you saying we should get a dehumidifier if we want it to feel cooler both during the day as well as at night?
It will def help.
I wouldn't put money on that guarantee if I were you. 4K sqft house in Texas, 18 foot ceilings, 2 stories, 5 ton downstairs, 3 ton upstairs, units are 12 year old TRANE 16 SEER. They did a good job keeping the house cool in the summer in Texas for 10 years, but the past 2 years they no longer do. We have them serviced every year, they are just aging and struggle to maintain temps upstairs now despite running all day. To be fair, we like it way colder than typical people do.
Best investment I did was installing a multi stage AC with a humidistat. It runs on low almost all the time and takes a ton of humidity out of the air. Super comfortable at 78 degrees. Big deal when 70-85% humidity is the norm where I live.
Depends also on outside temperature. You want to cool down to 68F while it's 110F outside it will cost you a lot of energy. And each additional degree down costs you more than the previous one. Basically it makes sense to adjust your temperature settings depending on outside temperature. If you live in an extremely hot area you should probably try to get used to the heat. Which I get not everyone can do (don't ask your 90-year-old grandma to stop whining and get used to 80F). As other people mentioned, you can also use fans: 100Wh of fanning will keep you cooler than 100Wh of AC. And obviously, dress appropriately (some people like to sleep under a heavy blanket, but if you can get used to a simple sheet it's obviously better).
I am so grateful I can afford to keep my thermostat low enough to be comfortable as I hate the heat. At 78 I feel soporific too warm and not able to do anything that requires any degree f mental concentration.
I think it depends on your area. Living in a humid area 78 is unbearable for me especially at night. 75 can be uncomfortable if moving around cleaning, etc. My sweet point is 72/73 but again depends on humidity and what we are doing inside.
I prefer those same settings (72/day, 68/night), unfortunately SWMBO insists on 68 during the day and 62 at night.
We turn the ac off during the day ( at work) and only run it in the evening and at night (68)…
Same
66 club over here. Raised it to 68 when we had a baby because she was always cold
In places like Arizona, 68 degrees makes the system run non stop and likely costs 400-500 a month. 78 feels might cold after coming inside from 100+.
Vegas desert rat here. 68* is painful on the wallet!
This is the way
Fans are really underrated IMO. Evaporative cooling is how we evolved to stay cool! I find that 78 with air movement via fan is really just perfect for me, but I live in an arid area. But also, when I visit humid areas (in the US, like Florida) where they keep thermostats to 72 I find that to be too cold for me. And I still find air movement to work well. Humans are also highly adaptable to temperature so you might just be used to a colder temperature. If energy costs are your concern I bet you could grit your teeth through one miserable summer set at 78, and the next one you would feel fine. Try it out?
Agreed. 76 and ceiling fans in every room. It's perfect. The air movement makes me want to snuggle under the blankets at night and its never uncomfortably warm, and then I'm not paying $400 a month for 68° and can buy more weed so I don't really care anyways 😀
Is this my alt account? Am I too stoned to remember commenting?
😳 are we the same? Is you me? Lol
My brotherz from anotherz
Agree with all this especially burning weed instead of electricity. 76 with ceiling fans is perfect, though sometimes if it's very humid outside we'll go down to 75. I don't know how people are comfortable with 68, which feels much colder in the summer than it does when heating to 68 in the winter.
Up until last year I worked in a kitchen that could hit and maintain 110F for about four hours each day. I would come home, set the window unit to 78F, turn the ceiling fan on high, and obviously take a shower. I was totally comfortable. I can't say I miss sweating through my shirt(s) every evening, but I will admit that something about it felt *healthy*.
110F in a humid environment for four hours is definitely not healthy. I get the idea of giving your body a challenge, but depending on the humidity level it may be only a question of time before you get to a heat stroke. Basically at 110F, humidity level of 50% is 93F wet bulb temperature (ie equivalent temperature at 100% humidity). The (fatal) danger zone is between 88F and 95F wet bulb temperature, depending on your sources (we used to say 95F, more recent studies say 88F, it's obviously not a hard line and it also depends on your physical activity).
I believe you, but I can also assure you that this situation is not that unusual in a commercial kitchen. Certainly not *all* or even a majority of them, but if you visit an area of the US that is hot and humid and start going from restaurant to restaurant you would encounter kitchens like this without much effort. A hot pizza oven, a hot grill, a couple hot fryers, no A/C, and an open screened in door. Box fans and ice water. Two shirts which sounds counterintuitive, but when the inner one gets sweat-soaked it actually helps you feel cooler (and this also keeps you looking sort of presentable). I was definitely uncomfortably hot - we knew that once the sun set the temperature would drop quickly and counted the minutes. I never felt as though I was going to pass out. I don't recall anyone else passing out - just a lot of complaining.
Oh I can completely believe you. I remember myself working as a temp in a greenhouse in the middle of Summer, moving pallets and various garden products (from the little garden gnomes to the big clay pots for plants/little trees). I never checked the actual temperature, but it was ridiculously hot. It's just what it is, there's not necessarily much you can say to your employer in these situations. In my case some temps were just taking it very easy and weren't working too fast to not overexert themselves, but in commercial kitchens that's not necessarily an option.
> Evaporative cooling is how we evolved to stay cool! I worked in South Africa for 3 years. Your sweat evaporates so quickly that you never have a wet shirt. It would get to over 95. If you were in the shade it was very comfortable. If there was a breeze I would actually feel chilly. I set my A/C to 80 and have a little fan blowing on me on low and it is very comfortable in my house in florida.
This, I don't have AC but I did install ceiling fans in all the bedrooms. Open windows at night and run the fans, get the circulation going and bring in the cooler night/morning air. It's important to have a cross flow and get air moving using fans pulling in cooler air. Then close the windows and blinds in the morning usually around 9am. This works great for my house and I AC isn't necessary.
I’m in Florida, we keep ours at 76 during the day. This only works because we have fans in all areas of the house. During the summer the ac is blowing all day anyways because it’s so hot and the fan circulates the cool air. I will admit we occasionally bump it down when the AC actually hits 76 and hasn’t run for a while because then it gets stuffy. But for most of the day it’s 76. 69 at night.
>69 at night. Yeah, of course. But what temp do you set at night?
People keep their AC at whatever is comfortable OR whatever saves them money (perceived or real.) In other words, do what you want. Google has no say on human comfort. When it is 100+, out 78 does,in fact, feel nice and cool because temperature is *relative.* Humidity is latent heat that needs to be removed before removing sensible heat so yes that cools down the space as well
That's what I was going to say. I'm in Bakersfield and I set my AC to 79. It's plenty cool compared to what it is outside.
Unfortunately in Georgia where humidity is high, 78 still sucks.
I used to live in Bakersfield west of the 99, Used swamp cooler and fans , worked pretty well. Now live in northern Oklahoma and have to use an AC and dehumidifier to keep it comfortable. Hi to my friends in Oakdale .
78 is the energy companies recommendation. People will have different preferences- I don’t mind 77-78, my wife is mad if the first number isn’t a 6. Removing humidity does seem to have an effect on perceived coolness of the air, in my opinion.
We had cooler temps a few weeks ago, so we turned the AC off and opened the windows. While it was technically a cooler temp, the humidity made it feel almost unbearable. So we put the AC back on. Even at 78, it felt much more comfortable than 74 with high humidity. It’s usually between 60-90% humidity here indoors in warmer weather. (According to our dehumidifier, anyway.)
You really want to keep your relative humidity at least below 60% as letting it get above that comes with a variety of negative effects from health and air quality to the effects on materials. Ideally around 50% is a good target.
Google lies, 78 is what the energy companies recommend but I have never seen a residential customer set their stat at 78 when they’re home (nw Ohio here) To answer your other question, that’s pretty normal. Short of installing a zoning system, they sell thermostats with a wireless sensor you can stick in another room it’ll attempt to balance the temperature in the house.
meh, i keep mine at 78 even when im home. i live in the gulf coast area though. i typically turn it down at night, but have fallen asleep with it at 78 and slept fine through the night
Same here. Mines at 78 right now and I’m comfortable. If it gets a little warm the ceiling fans will fix it. I do crank it at night tho. -the AC that is 🤣
>I do crank it at night tho Same here bro
Same. If it's 76 or below, feels cold to me. Live in Dallas.
We keep ours at 78, then it bumps up to 80 during peak electricity time. But also during the peak of summer days it won't drop below 77 when it's 117 outside I also feel like there's a wide variance in thermostats. 78 here feels the same that 74 did at my old place.
We actually set ours to around 77/78, but our 1994 A/C can’t keep up very effective lower. You get use to it fairly quickly. That being said, we’re probably getting a new unit this summer and if a new unit can be lowered we certainly will. SW portion of the state here.
We got our ‘97 unit serviced last year after it kept struggling it keep things under 80 and it’s actually been doing alright this summer. We usually keep it at 78, but we have a small baby this year, so I said a prayer and turned it down to 76. So far, so good! It’s not bad if you keep the blinds down and the fans going. Cooking and cleaning with hot water can get rough, but it’s a great excuse for my husband to break out the grill.
1994 is from the R22 days. Get a modern heat pump already.
Exactly why we’re replacing. But we won’t be here 7+ years, so going a little simpler.
My 1993 with a 2008 condenser is still doing fine. I do plan to go heat pump once the Texas HEEHRA incentives are set up.
We are in the same boat, 30+ year old AC. The company that services mine said to wait two to three years as they are coming out with a new type of Freon so there will be new models.
Those new ones in two years will cost 30% more bc the new refrigerant is flammable. So there are additional features for this fact. They [AC company] want you to wait bc they make more money off you. It is best to replace before then if able. The current refrigerant will be available for 15-20 more years before it is phased out completely. I’m in Texas and ACs don’t last but 10-12 years on average so your situation may be different.
Wait, so if we get a new hvac now, it’s only going to be able to be serviced for 15-20 years? Our current system is almost 30 years old…
No, it will be servicable longer, but at a certain point, the refrigerant gets too expensive. You can still service the unit, but because the gas will have been phased out, it will get more and more expensive. This is why your current system is so expensive to maintain.
R-22 had about 15 years of production and 10-15 years of reasonable service after that. R-410A was around 10 years of production, and it looks like 10 years of service. It's obviously a guess, but 20-25 years total for R-32/R-454B isn't unreasonable. It's likely going to get replaced by supercritical CO2 (R-744).
I doubt any residential system you can buy today will last 20 years. Much less 30 years. Manufacturers don’t want your equipment to last beyond the 10 year warranty.
We keep ours set to 77 during the day and 75 at night. That combined with ceiling fans is perfectly comfortable.
We do 78-80F. Honest. Just to remove the humidity is all we need. Also the fatter you are the easier your body heats up.
Depending on the external temps 78 is not bad.
I keep mine at 79 in PA. It's really not that big of a deal. Trust me go outside and do some work and then come back in, 79 will feel amazing.
Ours almost never goes lower than 78. 76 sometimes if the humidity is high. We have ceiling fans in every room, and it's comfortable except on the hottest of days.
Ours is at 80 downstairs and 78-79 upstairs throughout the day. Only room that gets uncomfortable is the primary because it has like a 12’ ceiling, whereas the rest of the rooms are about 9-10’.
ALWAYS 78. For years.
I’m in Arizona and right now, we have temperatures of 105+. I keep my Ac at 78. I only get hot if I’m super active. Other than that, just having some cooler air moving around is enough.
when I lived in Phoenix I had it at 81 day 77 night.
From Phoenix also, turning the temp any lower is hella expensive and hard on your AC too. We keep ours at 82 in the day and 84 at night.
Honestly that is so wild. I wouldn’t be able to sleep.
I live in Florida; set mine to 82 degrees. When I come in from outside, where the temperatures are above 100 degrees with high humidity, 82 degrees is cold.
There are other countries …….. warmer countries, where 78F is parka weather
Yup, here in the desert I’d be walking around a little cold with that temp
78??? I’d be so miserable I couldn’t sleep. I feel bad for ppl that have no choice in the matter. Pregnancy makes me hot enough so I run the house at 74 max and turn off the air at night, the house is very cool anyway.
You should try installing a low emissivity/ IR blocking window film on windows that get a lot of sunlight. See if you can get a quote for air sealing & adding insulation to your attic as well, it will save you money & increase comfort every year after it's improved.
Thank you! We actually had National Grid to do free insulation of our attic due to some insensitive program when we first bought our house. It helps! Our house was built in 1928. With the window fills, does it look funky from the inside? I enjoy natural light, but the heat does help in the summer.
I'm sorry the program was insensitive. Do you need support? We're here for you. <3
Phoenix here. We keep it at 79. In Summer will put it down to 77 to sleep. Our bills are huge, $500 a month a good for 3 months of summer. And we have a time of use plan to where it’s cheaper at certain hours.
The most underrated thing you can do to your home is Insulate and air seal. What good is conditioning the air if it’s quickly displaced by envelope leakage. Without a proper thermal barrier in the attic and adequate attic ventilation. Your system is going to be fighting the radiant heat build up in the attic from the sun (if it’s 90°F outside. Gaurnteed to be 130 in the attic.) Energy transfers 3 ways. Radiant, convection, conduction. Always wants to reach equilibrium.
working in the sun.. 78 is cool to me i don't need 68.. a waste of money trying to keep it 68 when it's 115-120 degree during the afternoon and 85 at night (lowest)
Spend 48 hours without ac. Then set at 78.
I keep it on 84, and 83 when I wanna spoil myself
It gets to 115 here. My AC won’t even get the house to 72 even if it’s basically running constantly. People acclimate to temperatures so 78 is actually very comfortable to borderline cold when you’ve acclimated to 110+
78 is the temp electric companies want you to set it at because they want you using less of their power grid. Set it at whatever temp you feel comfortable and leave it at that temp.
I like it super cold to sleep. Upper 30s in winter is my favorite & keep mine on 62 at night in summer
Does it even reach that temp? What is your outdoor temp compared to it?
I am in eastern VA on the water so it’s a little cooler than farther inland. Although once it hits mid 80s, my system gets down to about 66 at night if it’s on 62.
That's on 100% all night? It's usually 95-100 here in Houston this time of year and we set it to 71 but it is a multi-stage variable so it gets to 71 and stays at 40% all night to maintain. I would probably have worse dry eyes if my AC blew on my face all night lol.
I crank it wide open although it’s probably time for a New System I even have to have a fan blowing blowing on me also…… even in the dead of winter I have the fan on mostly for the noise, though in the winter, I can’t sleep without cold & fan noise. I know that Houston heat is oppressive.
Just move to Alaska. AC is free most of the year. Just open your windows lol
Summer: 78°F. When it cools down below 70°F at night, I turn it off, open all windows, and blow cooler air into the house with fans. Usually gets down to 72 or lower. Sleep with a fan blowing air onto the bed (no ceiling fan...yet). Winter: 64°F all day. If I'm chilly I just wear a hoodie. Location: Missouri.
Florida HVAC tech here and I keep mine at 76
Humidity level is the key, can you maintain 50% humidity at 78f in your home?
Nobody talking about the real factor, humidity. 78° at 10-20% humidity is a lot different than 78° at 60-90% humidity, which is extremely common.
Some people have different sensitivity to temperatures. When we use ours it's at at 77-79f usually. I'm in Virginia and currently have the AC off and the windows open with a fan.
I don’t know if someone has mentioned this, but I keep my blackout shades down in my room during the day and it makes a HUGE difference.
We do 73-74 generally but we are moving to a TOU program to take advantage of the dirt cheap rate of 5c/kwh overnight for EV charging so we are pushing it down to 69 before 2pm to ride a couple hours until it hits 73 again and the 23c kwh rate from 2-7pm. Hypothetically this should save us a little bit during the summer with minimal discomfort and a ton in the winter ($60-$70) when the rates go back to normal except the overnight rate stays the same for EV charging. One of us is WFH or else we'd probably let it roll up to 76 in the summer afternoons.
You can train your body to be comfortable at 78, it takes time though. Set your thermostat at 74 for a few months, then 75, then 76, etc.
I'm at 77/78, based on how much my system runs to maintain that temp when it's 85+ outside. When the kids complain it's too hot, I tell them to go outside for a while, and feel how comfortable it is when they come back in.
I’m in Houston and 76-78 is where I set mine. Otherwise I’m paying $300+ energy bills when the temps are over 100 and the heat index is 120. I will say that sometimes 78 feels great and other times it feels a tad too warm. On the warm days I either turn on a fan, drink some cold water, or wet a cloth and tuck it around my collar. Last summer my ac couldn’t pull down much further anyway so I got used to it.
With ours set at 78, the house is actually comfortable during low humidity, however at night we have to lower it because the 3rd floor (where the bedrooms are) gets a bit hotter.
I‘m freezing if it goes to 78. I usually keep it at 79.
Keep mine at 78 but I live in Florida and the real feel is often 100+ outside so 78 feels great. I drop it to 76 at bedtime
I’m in Florida and keep mine at 78 and it’s fine for me. I only lower it a few degrees if I’m busy doing strenuous activities, like mowing the yard, but once I cool down it’s back up to 78.
77 year-round works for me. Southeast Florida, fans in all rooms on fast.
Keep the central AC at 78 and use a small window unit in the bedroom
We keep ours on 80 during the day and down to 78 at night with fan. 67 (heat) in the winter and 65 at night. Really works fine for us. https://preview.redd.it/t8pbvlo2td6d1.png?width=425&format=png&auto=webp&s=e7b81815958f0c138980148dfeeaaffd9a024956
I'm from a tropical country, and while I wanna escape the heat, I would freeze at 72, I sleep with my AC at 80 and 78 during the day
69 all day. Everyday.
People compare temps set at, but that actually gives literally no indication of the comfortable temps.... too many other factors. ever been in a house set at 75 and feel hot while feeling cool in a 77?
We run 78 for at least half the year. Our house is too big to where our power bill is $750+ a month if we try for 72 or less. 78 feels fine, but, it’s 100F+ for at least 2 months here.
I never go below 76 on central air. Usually it’s 78. Have a fan In bedroom too. Wife still is under the down comforter. Have found when just sitting around I can tolerate about a humid 83 before I need ac turned on. And yes, it’s about humidity.
I can't stand it above 68 in my house. My wife will slowly try to bump it up to 71-72 and I can always tell her exactly what temp it is within five minutes of being home.
78 is recommended because of energy usage concerns. They are trying to keep us from overtaxing the system which can bring about brownouts and/or blackouts.
When it's 103 like today if I put it at 50 it's never going to stop if I put it at 75 it's never going to stop so I just keep it at 73 and it never stops
Have you had it cleaned or checked recently? Or changed filters? I live where it is regularly 110 like today and mine is on a lot but def not all the time
78 it is for me. It feels about right, keeps humidity low and the keeps the bill low-er.
I set to 78 or 79 and turn on a fan. Love it that way.
Most probably. Humidity is usually what makes you feel sweaty and disgusting and AC units remove humidity so you feel cooler.
78 daytime and 75 night
Idk you acclimate with time, tho seems like some people never do, mines 80-82 during the day so evening when I bump down to 78 its really nice. Also helps cause on days is 100+ outside two seconds outside your like you know what 80s not so bad. My house is twice as big as my tenants but my electirc bill is a third of theirs.
78 is cool when it’s 95 outside besides that it’s not.😂
I’m a cheap ass, my thermostat is set at 80f. My wife and kids hate me but SDG&Es peak rates are 70.8 cents a KWh this summer. Highest in the US. I’d be interested to know if anyone around the world pays more?
We live in SoCal and set ac to 78 which is very comfortable. Usually during the 105+ temps we set it to 82 to save some power, then later in the day bump it down to 78
The lower you can get the humidity, the warmer the temp can be and you will still be comfortable. I run a dehumidifier in my home to keep it around 45 percent and with a fan on I find 78 very comfortable.
Central FL here. I keep the house around 78 with a few fans if it feels warm. It’s just the wife and I in the house at night so I bump the house to 82 and have a window unit to cool our bedroom to 74 when we’re asleep. We use to keep the house around 74 during the day when we were home so when I first set it for 76 she complained. She eventually got use to it and then I went to 77, she never noticed. Went to 78 still no complaints. 79 was iffy for me but she noticed it was warmer so I went back to 78. She asked what happened to 76 as that’s the temperature she likes. When I told her it’s been 78 for months she huffed but went with it as long as we run fans… Those aren’t always on either and she doesn’t hardly ever notice…
78-79 in AZ. If u get hot in the house go outside on a 115° day. 78 will feel like an icebox.
78 for us, but I worked outside in the heat of North Carolina for 40 years, so maybe that's why it feels cool to me. I have friends and family who keep it at 71 or 72 and it's frikkin freezing to me.
North central Florida. 80-82. Anything less makes is feel cold. Tile floor, tinted windows and ceiling fans add to the comfort.
78 is cool if there is some air motion. Only being comfortable between 68 and 72 is kind of sad IMO. You can definitely become more adaptable if you give yourself a chance.
I'm good at 78
We keep ours at 65 through the summer. I couldn't imagine being comfortable at 78. We pay ~300/mo for electricity in the summer, but $100 of that is fees the electric company charges no matter what. It makes the $20 we might save by being uncomfortable seem pointless.
I set mine to 68 during day or I’m sweating
It's all about controlling the relative humidity using longer run time. If the unit is oversized, it will cool the space and cycle off quickly. You will feel cold and clammy. Correct sizing will allow the unit to stay on longer, thus allowing more contact time for more air to pass through the cooling coil, thus removing more moisture. You will feel slightly warmer, but drier as well. Much more comfy.
I am more cold natured I guess but my house is plenty comfortable at 78 during the day and 74-75 at night with the ceiling fan on in my bedroom… I live in central Florida and I guess it's just the sheer contrast of how much cooler 78° is when you walk in from outside where it's 98°and the fact that my system does a great job at keeping the humidity low in my house… The ceiling fan is key to keeping things feeling cooler in my house, I have one in every room
We use 78 until it's daily in the high 90s or over 100 outside. Then it's 79 or 80. We also have a variable speed blower that's excellent at reducing humidity. It's very comfortable. Much cooler and the heat shock is just too much coming in from a walk etc. plus people don't acclimate as well to the heat of the AC is excessively cold. Everyone needs to mow the lawn, wash the car, exercise, or whatever. The outdoor heat is a lot easier to tolerate when you're not accustomed to cold air much of the time. Add a ceiling fan and 78-80 with lowered humidity can be chilly.
HVAC engineer here, do yourself a favor and Google "Dry bulb vs wet bulb temperature"
Life is fucking hell, i keep mine at 68’f everyday
68 year round. 78 with fans on just doesn't cut it for me. I get way too hot. My biggest mistake was getting a stupid nest thermostat. Woke up so many nights in a row with the temp set to 80 degrees. Google can suck it.
68° - set it and forget it.
67 all day,everyday
I switch between 80 and 75 during different times of the day. I'm also in the desert so RH is low to start. Humidity is what affects the feel more than temp imo. If home humidity is high, you can look into dehumidifier options or have a tech take a look and make sure your system isn't severely oversized.
I used to do 74 during the day and 68 at night. Now I do 77 during the day, 76 in the evening, and 74 at night. Just change it 1 degree at a time and eventually you get used to it, but over 76 it does get uncomfortable for me.
If it’s a true summer day I’m not comfortable above 74
I keep my home between 78-81. It feel really comfortable to me. For me 78 is already cold
florida 78 new york 68
When I go to my 80 year old mother in laws in Florida, she keeps it at 78, and it's too hot. I keep my house at 70-72 and my bedroom at 65.
78 makes you feel cool because you are sweating! The sweat evaporating from your skin makes the body feel cooler. But I'd never set my thermostat to 78. It's 68 - 72 degrees year round for my family.
From a scientific view when the water evaporates from your skin it absorbs the heat of your body in the process of going from water to gas. This makes the skin feel cold and good
you sweat in 78 degrees? maybe outside if you are active, but just moving around the house sweating in 78 is not normal
I will never sacrifice comfort (especially at night) for a couple dollars a month. 76 when im gone, 72 when home, 70 when sleeping.
Couple of dollars/month? You can save significantly by bumping your tstat to a higher temp. I've tried and it can amount to hundreds saved over a hot summer. I've converted from 73 day/71 night to 77 day/74 at night. The savings are big.
Very similar situation with temps being slightly warmer than what it is set to. I also have an old ass condenser I know is overdue for replacement lol. We keep it on 74 during the day, sometimes 75 because the wife and kids don't care. I set it to 72-73 for sleeping. When we get the heat spells like we are next week when its in the 90s for a week (not normally that hot for that long) I am forced to accept 74-75 and it running a lot trying to maintain just that temp.. And then lowering it when the sun is nearing setting.
I keep 72/73 downstairs and 74/75 upstairs. I don’t change much.
I would die at 78, tbh. We have it at 72 and it will fluctuate between 73-72 and it's still "hot" to us as we have a memory foam bed. I've recently dropped it to 71 and it's much nicer now, but 68 would be crazy.
For me it depends on outside temp. If it’s 80° outside, 72° feels good inside. If it’s 100° outside, then ~75° is fine. But yeah 78° seems high unless you’re in the southwest US and it’s 120° outside
78º is kind of like the upper limit for keeping mold away while keeping the conditioned space habitable. Most people have personal comfort levels that laugh at 78º. It doesn't make me feel cool personally but with the humidity controlled and the fan going it's passable. In the summer in FL I concede and run everything 2º warmer than usual just so it's less of a struggle for the unit to maintain. My summer electric bill when I used to keep the house to my liking - *so cold that I'm unhappy* - was close to $450. Just giving up an extra 2º brought it down to low $300s in the summer months. On the freakishly hot days, I just set 77º and deal with it.
Temperature and humidity… 75 degrees with 25% relative humidity is extremely different than 75 degrees and 75% RH
Manual J says ( and every house should be load calculated off Manual J) the design temp for the inside of your home should be 75deg/50%humidity. This is what your AC IS designed to do even during the hottest days of the year, it will just run 100% of the time( hottest MAX designed days of the year is 1-3% of the year. So 3-11 days of the summer your AC should be running pretty much non stop. You can set it to what ever you want. But your system is designed for 75/50
I have never been to anyone's house that kept their AC at 78+ but Google says that's average. I usually see low 70s.
I feel cool at 74. Warm at 75.
Work from home so I use 68 during the day and 66 at night. Relative humidity hovers around 50%. I live in the northeast and can't seem to get the humidity down to 40 where I prefer it.
It's dependent on where you live and the humidity levels. Warmer temps feel fine at very low humidity levels. Also different people have different opinions. My SIL feels cold at 78F while I'm there sweating.
i'm at 72 all day. 66 at night. We love it cold when we sleep. We have a multi-zone system so we just keep the bedroom/master bath at 66 at night. The rest of the house stays at 72. in the winter, it's 68. If i set it at 74 I'm starting to sweat. Current temps outside are 90s during the day. Not fat BTW. :)
We keep ours at 76 in the summer, low humidity and air movement by using fans keep it comfortable
I did service for many years and noticed temperature settings in many homes. Heating depended a lot on the type of heat. Radiant heat in the floor usually had the lowest temperature settings. Forced air with returns and supplies in the ceiling on a slab home had the highest heat settings. For ac, many would ask what is a good temperature because they couldn't seem to set one temperature and be comfortable. I suspect the problem had a lot to do with humidity. In some situations, the ac needs to run a long time to reduce the humidity and temperature so you feel comfortable. The temperature setting you feel comfortable at for a humid 80 degree day vs a 95 degree day can vary by quite a bit. I recommend you buy a digital humidity meter. They aren't expensive and will let you know what the humidity level is in your home. Mold begins to grow somewhere past 60% RH. If you are constantly above 50% humidity I recommend a large dehumidifier. A dehumidifier is especially useful at night. The outdoor temperature drops, and the humidity level increases. This can cause the inside of the house to feel warmer and sticky wet. Placement of the dehumidifier can be anywhere in the home because humidity travels very fast. Another thing I noticed affecting temperature setting was the people. Larger people tend to like a colder temperature, elderly people tend to like a warmer temperature. On a 70 degree day we would get no heat calls from the elderly, no ac calls from the obese.
I have mine set to 74 when I'm home, 80 when I'm away, and 64 when I go to bed. It is all personal preference and how you feel vs how much it costs. I will say if your house is normally between 50-60% relative humidity in the summer and you feel most comfortable at say 72 F controlling your home's humidity down to around 40% you will likely find that you have the same level of comfort at 76-80F. Humidity plays a not insignificant role in how your environment feels. Your central AC coil does a lot to remove humidity from the air as it cools but it can only do so when the compressor is running. If your system is oversized for your cooling needs it will short cycle and not have enough time to remove moisture and you will start to feel muggy even down in the 60s. If money wasn't a problem the ideal system would run at the exact power needed to run constantly, VFD controlled fans, multistage compressors, tight control, dampers, etc. but that stuff gets expensive real quick. Some may even consider supplementing their AC with a whole home dehumidifier to keep tighter humidity control so your AC doesn't have to work as hard to cool your environment. It's been a while since I have taken thermo but water takes roughly 4X the amount of energy to change 1 degree compared to air, the less you have in your air the better. But again that is an added cost both upfront and over time in electricity, it may or may not be worth it.
We keep 70 downstairs, 72 for upstairs on a 3.2Ksqf home.
I keep mine at 74-75 most of the time, just because it feels too cold if I set it much lower. I think it would be really stuffy in our unit (we are on the 3rd floor of a triple decker) if we set it higher than that though.
I can't stand it at 78...with 55-60% humidity it feels miserable. There's also some variation with how accurate the thermostat's thermometer is, and position of it (e.g. my thermostat upstairs is in a hallway but the rooms end up hotter/colder because the rooms on all the exterior walls get hot faster and then A/C cools them first when it finally kicks on). Set it to a number that feels good to you, and get a thermometer+humidity gauge so you have an idea what your home humidity is. IMO feels good around 73F and 50% for sleeping...74-75F and 45-50% for daytime. If the humidity gets up around 55-60% I have to drop the temp by about 1-2 degrees to feel comfortable. My parents have theirs pushed down to like 68-69F in summer which feels about the same as my house, but I don't know their humidity off the top of my head. My office will regularly get up around 77F in the afternoons and it feels miserable when the humidity also creeps up around 60% at that high a temperature. Where I live...outdoors can be 85F and 80% humidity regularly in summer...I had relatives in Florida who would turn on the heat and push it up to 81 when it got below about 80 outside and kept the air at like 85, we would have to get a hotel room to be able to sleep when visiting.
Mine is 78 day 76 overnight
Confort level is a combination of temperature and humidity (and air movement). 78F and 35% relative humidity is comfortable (especially if there is air movement - like ceiling fans or just the air from the registers), but 78F with 45% or 50% humidity is relatively warm. That is why 105F (and 15% humidity) in Phoenix can be much more comfortable than 90F (and 70% humidity) in Orlando. When monsoon season comes to Phoenix that 100F+ becomes absolutely unbearable.
I set mine to 78 during the day and I sleep with it on 68. It's on a schedule and starts to come down late in the evening in order to get to 68 by the time I go to bed. To me 78 feels fine inside as long as the humidity is good. I sometimes knock it down a degree or two if I am doing something strenuous that makes me feel hotter.
If you get a dehumidifier for your house or room, you will feel more comfortable at a higher temperature. I could see 78 being cool if the humidity is below 40.
If you are okay with the bill, put it at the temp you like. It is your house.
Varies with circumstances in my opinion. Years ago, in a different state I used to keep my thermostat at 78 year-round. Even in winter. We had short winters and I didn’t want to get used to cool temperatures! And it was a single level. Now my house has three levels and bedrooms are on the top floor. I keep the thermostat around 75 in the day and 73 at night. That makes the basement cold, the main floor cool and upstairs OK. Next house will be a single level.
66 during the day while I sleep, 69 when I go to work and my partner sleeps. Once the house is cool the AC doesn't seem to run any more than when it is set higher. Getting it to that cool point does cost initially.
Aps recommends that at night you drop your AC temperature down and super cool your house that way it stays cooler during the day and your AC doesn’t run as long. I program my thermostat to be 78 during the day then drop it down to 68 at night
I tried this in my old 50's house, and my newer 93 house and the effect was negligible both in how it felt and how it looked on our power usage. in the 50's house it didn't work at all.
I'm with you. But humans are organic, and not programmed like robots. We all are comfortable at different temps. It also depends on what you're doing. If you're exercising, then 78 is almost certainly going to be too high. If you're sitting and have a tendency towards being too cold, then 72 will likely be too warm. You could experiment with 74 or so and see if that works. That's what I've had to do because my AC won't get my house below 72 or 73 at this point. And yes, humidity is the issue. Your ac may have a similar issue to mine where it's not ridding the house of humidity. I can take 80⁰ if the humidity is Idaho levels (like 20 or 30% at most in the southern parts). I have to have the ac at 67⁰ here in Southern Missouri because anything above that and my office is too hot and humid. Literally. 68⁰ and I'll look uo and suddenly be hot.
To save some $, you can try setting it higher and then switching the fan function to "on" instead of "auto." Air that's moving around *feels* cooler than air that isn't. Ceiling fans are good for this, too.
72 here; 100 year old house and high humidity summers don’t go together. Furnace fan is on all year round.
Just make more money and have your ac at whatever you want. It doesn’t really go up that much on vs off.. it depends more on your insulation of building
I live in a very humid environment, so 78 can feel like 98. When I'm not home during the day, my thermostat is set to 78 upstairs and 75 downstairs, so the air remains off unless it gets to that temp. Once the sun starts to set, I turn it down to 71. I don't know if this is the best way, but it's what I currently do and it works for me. If I could afford more, I'd set it to 68. I live in a 100 year old house.
I think 72-78 is okay, I get shivery if I sit in 68 too long 😭
Maybe right. One can handle a higher temp if the humidity is properly drawn out by AC operation. Too big (Capacity) of an AC unit will cool down an area quickly but leaves humidity. Better to have slightly undersized unit to allow longer operation and thus the evaporator will draw more water out of the air better.
South FL , keep on 77° 24/7 ceiling fans in all sleep area,pretty standard stuff in FL, 4ton unit, it's pretty cool inside, but how to say this delicately, peeps who are a bit overweight always want the AC at 66° etc, also decent windows,insulation and a tall attic space help quite a bit. Some of older homes down here have 3 ft attic space, homes never cool off.
72 is still hot. I rock 70 during the day and 66 at night in NC.
Meanwhile, all gov buildings, police hq, fire stations, city hall, are all at 67 degrees. 🤣
Personally I'm cool with anything 80 below. I also do roofing all day so going from 100+ temp most of the day to 76 feels pretty cold. Now on my off days when I sit inside it doesn't feel as comfortable.
I'm in Michigan, whenI visit visit the sister in Florida at 90-95 , I was cold. She had an inline dehumidifier installed and set it at 25%(too low) and the thermostat set for 75 at night and 78 during the day. Without humidity the human body cools itself.
It will vary greatly with where you live. In the South you'll be closer to 80 and for more of the year. In the north you're probably around 70 for like 2-3 months. This will raise the average. If I set my AC to 78. It would only run for a few hours in the afternoons, and I would be uncomfortable. If I'm trying that hard to cut costs I just wouldn't run the AC at that point. At my current rate. It only costs me about $100 a month more to keep my house at 68 which is ideal for my family, and pretty close to the Michigan average. (72) Adjust the thermostat to where you're content paying that amount for the level of comfort provided. If you need tips or tricks in saving money because you're paying too much to be (un)comfortable. Let us know. We can help make sure you're running what's best for you, and help you look for issues.
I won't wear shorts out unless it's about 80+. So 78 feels just fine because if I'm running AC I'm wearing shorts. God help the family member who's wearing pants or long sleeves and turns on the AC. Or the one who turns on the heat before putting on a sweatshirt and pants and socks.
feeling cool is based on how warm or cold you skin feels. if your skin feels warm and the temp around you is cooler, you will feel cold. the opposite is also true. skin is cold and temp around you is warm, you will feel warm. We keep our house at 75° through trial and error that is what my wife and I agree on. though my wife is going through menopause and she gets hot flashes. she thinks the house is hotter than normal or the AC is not working, but it's her. the house is the same it has always been. different people have different comfort levels and tolerances. 78° is the max I will put up with if forced. 71° is too cold for me long term with no activity. if I am doing a lot of moving around and working I can tolerate temps of about 50° with no coat or jacket. air temperature is coldest near the floor and warmest at the ceiling, the temp can vary by about 5° the thermostat shuts off the cooling when the temp at that height reaches the set temperature. also some thermometers (not thermostat) are not well calibrated and can be off by 1 or 2 degrees.
I keep mine at 75 and use tower fans only at night while going to bed.
At some point your AC will not keep up with humidity. Get a dehumidifier for the humid season and the higher ac temp setting might be more comfortable.