explain why same temp feels different

Messages
764
Location
NJ
We have central a/c in our house. I leave the temp at 71 degrees during the day all year round. In the winter with thermostat at 71 degrees I feel almost cold. While in summer I feel almost hot. House has insulation and wrapped in tyvek. Is there a real cause for this or is it just in my mind, cold in winter and hot in summer.
 
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40,718
Location
Great Lakes
Some of it has to do with humidity... higher humidity is perceived by your body as "hotter". Typically in the summer, humidity is high, even though your AC tries to dry the air out, but it's still higher than dry winter air. http://science.howstuffworks.com/dictionary/meteorological-terms/question651.htm With that said, I've never personally felt that 71F is almost hot. During summer, we keep our AC around 75-76F and that feels pretty cold to us. But I guess we're all wired differently. What is the humidity in your house during summer with AC running? If humidity is still rather high, maybe your AC isn't working as well as it should be.
 
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13,194
Location
Maricopa Arizona
If I can be serious for a moment. A likely theory is the outside walls are of your house are cold in the winter, hot in the summer. Radiant heat transfer from you to the wall is posive in the winter you're warming up the walls - feel cold and negative in the summer. Then factor in that more humid air does hamper the body's efficiency to shed heat and in the summer as a rule the air is more humid. Thus you feel warmer in the summer when the gradient temperature is the same inside as winter.
 
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7,485
Location
S California
Your core temp, humidity, level of activity, mental distractions, digestion, floor temp, shoes/sock and clothing, air movement and thinking about your next oil change.
 
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3,435
Location
FL
The humidity plays a big part. Im the opposite...in my house with AC on in summer.....74 is nice and cool.....if I put the heat on 74 I would be burning up. Im also in Florida.....so very rarely do I need to put the heat on.
 
Messages
14,505
Location
Top of Virginia
It's the opposite in NC as well. Our thermostat is set to (and it maintains at) 75 deg F in the summer. Winter temperature is set to 68 deg F. Both feel similar to us.
 
Messages
1,086
Location
Gulf Coast
Wife and I were just talking about this the other day. Except we feel a difference from day to night. Right now thermostat set at 75 during the day is nice and cool, but at night if left on 75 we get hot. Why? Don't know...so we've always turned it down to 73 or so. Feels the same as 75 during the day. Weird...
 
Messages
40,718
Location
Great Lakes
Originally Posted By: stranger706
Wife and I were just talking about this the other day. Except we feel a difference from day to night. Right now thermostat set at 75 during the day is nice and cool, but at night if left on 75 we get hot. Why?
At night, outside temps drop. With a smaller temp difference between outside and inside, your AC comes on less frequently, leading to more humid air inside, which your body perceives as "hotter".
 
Messages
6,367
Location
Midwest
There are a number of reasons why a house, when the thermostat is set for the same temperature, will feel different between the summer and winter. The location of the thermostat has a lot to do with it. Since it's normally located on a central wall it doesn't reflect the heat or cold pressure on the outside walls, which can make a significant difference, especially in an older, poorly insulated house. Unless it's a well insulated home, the temperature at the thermostat may be several degrees different than the temperature radiating from the wall. Windows also have a lot to do with it. Older, leaky windows that cause cold drafts in the winter also cause warm drafts in the summer heat. Walk up and place your hand on an old, single pane window on a sunny, 90 degree day and it will feel much different than the same window on a cold 10 degree day. That temperature difference radiates into the room and can make a room warmer or colder than the temperature near the thermostat. Add to that cold, unfinished and uninsulated basements that radiate cooler air up to the main floor of the house and help keep the floors colder in winter, poorly designed HVAC systems that don't control humidity and don't get proper air flow to all the rooms, and little or no insulation in the walls, ceilings and floors. All can combine to create a house with very poor climate control that makes 68 in the winter feel cold and 68 in the summer feel warm.
 
Messages
1,468
Location
Perris, CA
I think the perception is that anything cooler than outside air will feel "cool" and anything warmer will feel "warm." In the summer I'm perfectly happy somewhere in the range of 76-78. In the winter, about 70 will work. I'm sure part of it is mental as well. Also, the OP is in Arizona. What is this "humidity" you speak of?
 
Messages
593
Location
Al
North Texas climate. We use a programmable thermostat and during the summer we set temp to 77 daytime and 76 at night to sleep. In winter set at 69 daytime and 58 at night (although it rarely gets that low so our heat is basically off almost every night). As such my wife is always cold and I am always hot on a year round basis.
 
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Messages
211
Location
Sta Catarina, Br
As your username implies rsrsrsrs ... It depends if the A/C is trying to raise the temperature of if it is trying to decrease temperature. When it is raising, the most part will be going at the top of the room first (warm air raises) and you'll feel less the change until it blends. But warm air doesn't blend very well. When it's decreasing temperature the most production will go to the bottom of the room. Since we are living below the medium height of the room, most of the times, we will feel the change more pronouced when such changes of air temps is happening at the lower parts and the room. So, the AC efficiency is better and quickier when cooling then warming the ambient at our bodies level. That's why you feel more the cold at cold days at colder or lower parts ... That's because the temperatures indicated by the equipment is an average from where it's installed almost at top of the room and the 71 there isn't 71 at medium height ... If you can get me, because I took the red one, hahaha
 
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Messages
8,859
Location
Texas
My guess would be radiant heating through the walls and roof, as mentioned by dave1251. The office I work in has a flat roof with a suspended ceiling, and (in the old section) very little roof insulation. A few years ago, someone swore that they would feel a chill inside the building whenever a cloud passed overhead. We even ran a test with one of us in an interior room trying to detect clouds going over, on the phone with someone by a window. The guy in the interior room was right almost all the time. Interestingly, I generally feel exactly the opposite of you. In summer, I'm used to it being warm outside so 72 feels kinda chilly inside. In winter, I'm used to cold outside so 72 inside feels too warm. The office is 72 year round, and I hate it- I'm almost never comfortable. At home we pick about 78 in the summer and 70 in the winter.
 
Messages
3,877
Location
Alberta, Canada
I find it depends how often you go from outside to inside. You spend 20 mins freezing your nubs off come inside to a warm house of 71F. You get all cozy and warmed up after an hour or two, you glance outside and think about going back out, it will give you a shiver every time. You spend outside cooking in the sun, you come inside for some shade and cooler temps of 71F. You get cooled off acclimated after an hour or two you glance outside and think about going back out, it makes your sweat glands trigger a bit every time. It's half in your mind, half our internal conditioning/preparing to deal with the external temperatures.
 
Messages
593
Location
Al
Originally Posted By: Rosetta
As your username implies rsrsrsrs ... It depends if the A/C is trying to raise the temperature of if it is trying to decrease temperature. When it is raising, the most part will be going at the top of the room first (warm air raises) and you'll feel less the change until it blends. But warm air doesn't blend very well. When it's decreasing temperature the most production will go to the bottom of the room. Since we are living below the medium height of the room, most of the times, we will feel the change more pronouced when such changes of air temps is happening at the lower parts and the room. So, the AC efficiency is better and quickier when cooling then warming the ambient at our bodies level. That's why you feel more the cold at cold days at colder or lower parts ... That's because the temperatures indicated by the equipment is an average from where it's installed almost at top of the room and the 71 there isn't 71 at medium height ... If you can get me, because I took the red one, hahaha
Aha ...very insightful post.
 
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