Home comfort mystery

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Startled Cat
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Home comfort mystery

Post by Startled Cat »

I live in a large loft apartment with very high ceilings and many windows. This winter, being home all the time due to the pandemic, I decided to stay comfortable in my isolation and set the thermostat at 69F during waking hours, whereas I used to go slightly lower, and used to only run the heat during the hours I'm generally at home. To my disappointment, this isn't really doing the trick. When the outdoor temperature is relatively cold, I need to wear long sleeves at a minimum, and usually throw on a fleece on top of that. Even then, I often feel pretty cold, especially in the evenings. But on relatively warm days where the outdoor temperature gets into the 60s, I don't have this problem, and feel totally comfortable inside even with short sleeves. It doesn't make sense to me and I'm wondering what's going on.

I don't think it's due to uneven heat coverage. I've placed thermometers in the places I spend the most time, and they match the thermostat setting very closely. Most of the space in the apartment is a single cavernous room, with a lofted area. There is a single wall-mounted gas heater which blows into this space. The temperature throughout the common space seems to be reasonably uniform, except right by walls or windows, and I generally sit at least a few meters into the interior. (The bedrooms don't get good heat coverage, but that's a different issue.)

I don't think humidity is a factor either. I monitor humidity as well and haven't noticed a correlation.

I was open to the possibility that this is a weird psychological thing, but that doesn't seem consistent with the data. Often I don't know that it's a particularly cold day until I realize that I'm freezing indoors. And this pattern is so consistent, and not at all subtle.

I'm deeply curious to solve the puzzle of why 69F indoors on a cold day feels so different from 69F indoors on a warm day!
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serbeer
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Re: Home comfort mystery

Post by serbeer »

Because your outside walls temperature is affected by outside weather. You warm body radiates heat to the colder walls losing it more rapidly on cold days even if thermometer in the room shows the same inside temperature.

Put your face close to the outside wall on colder day without touching it and you will feel the cold on your face as your body will radiate the heat at higher rate.

The fact that wall area is large, and especially that there are a lot of windows, which are always colder than walls not insulated as much, magnifies the effect. You can use inexpensive consumer infrared phone attachment, eg Seek Thermal, so see a thermal map of your loft, the windows will stand out quite a bit.

The heat radiation effect will be minimized if you sit at the center of the room, and rapidly accelerate as you approach cold walls.

In the summer, the effect will be reversed, the closer to the walls heated by sun you seat, the hotter you will feel, even in seemingly comfortable room.
LifeIsGood
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Re: Home comfort mystery

Post by LifeIsGood »

You mentioned having high ceilings. Heat rises. I'd be willing to be a lot of your heat is up there. If you have a ceiling fan(s) they usually have a reverse switch on them and will push air down from the ceiling rather than pull it up.
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lthenderson
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Re: Home comfort mystery

Post by lthenderson »

LifeIsGood wrote: Fri Jan 15, 2021 5:36 am You mentioned having high ceilings. Heat rises. I'd be willing to be a lot of your heat is up there. If you have a ceiling fan(s) they usually have a reverse switch on them and will push air down from the ceiling rather than pull it up.
I have ceiling fans and have always heard and felt that in the winter months, it is better to have them working to pull the cold air up from the lower parts of the room and mixing with the hot air up near the ceiling. If you have them blowing down, just the breeze across your skin can make you feel colder since it is below your body temperature by quite spread. In the summer, you reverse direction and have the ceiling fan blowing downwards.
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Re: Home comfort mystery

Post by livesoft »

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corysold
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Re: Home comfort mystery

Post by corysold »

Humidity matters as well.

69 feels different depending on the humidity of the air. Perhaps a humidifier could help in the colder months.
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Sandtrap
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Re: Home comfort mystery

Post by Sandtrap »

Startled Cat wrote: Fri Jan 15, 2021 1:04 am I live in a large loft apartment with very high ceilings and many windows. This winter, being home all the time due to the pandemic, I decided to stay comfortable in my isolation and set the thermostat at 69F during waking hours, whereas I used to go slightly lower, and used to only run the heat during the hours I'm generally at home. To my disappointment, this isn't really doing the trick. When the outdoor temperature is relatively cold, I need to wear long sleeves at a minimum, and usually throw on a fleece on top of that. Even then, I often feel pretty cold, especially in the evenings. But on relatively warm days where the outdoor temperature gets into the 60s, I don't have this problem, and feel totally comfortable inside even with short sleeves. It doesn't make sense to me and I'm wondering what's going on.

I don't think it's due to uneven heat coverage. I've placed thermometers in the places I spend the most time, and they match the thermostat setting very closely. Most of the space in the apartment is a single cavernous room, with a lofted area. There is a single wall-mounted gas heater which blows into this space. The temperature throughout the common space seems to be reasonably uniform, except right by walls or windows, and I generally sit at least a few meters into the interior. (The bedrooms don't get good heat coverage, but that's a different issue.)

I don't think humidity is a factor either. I monitor humidity as well and haven't noticed a correlation.

I was open to the possibility that this is a weird psychological thing, but that doesn't seem consistent with the data. Often I don't know that it's a particularly cold day until I realize that I'm freezing indoors. And this pattern is so consistent, and not at all subtle.

I'm deeply curious to solve the puzzle of why 69F indoors on a cold day feels so different from 69F indoors on a warm day!
We have a similar problem in our home. It is about 5000 s.f. on 3 levels and "feels cold" in various areas when the temperature and humidity changes outside at certain low temperatures. We have wireless sender thermometers all over the home including attic, garage, etc, that send readings to a central unit called "Hal".

We also have a whole house humidifier at various times to keep it within a reasonable range.

***Actionable Solution to "getting the chill out of an area and out of humans as well":

* We sometimes use a heat dish for a little while wherever we are standing such as in the kitchen in the morning, in the gym room, etc. But not for the whole house since it has central heat on each of 3 floors.

We have several Presto Reflective Heat Dish portable 110v plug in area/space heaters that have worked well to move around wherever we happen to be to take the "chill" out of the air. It's a simple solution that's worked in any home we've had over the many decades. Sometimes Costco has them for a good price. One of our Presto Heat Dish's is over 30 years old (also from Costco) and still works fine.

Presto Heat Dish (around $50 or less is a good price, the oscilating one that looks like it but is not a Presto or all metalic is not a good one).
Some Amazon sellers price gauge them. We've tried tons of different types and these are very rugged and put out and direct heat excellently.
(Amazon product link)
https://smile.amazon.com/Presto-HeatDis ... 222&sr=8-2

Image
Last edited by Sandtrap on Fri Jan 15, 2021 8:06 am, edited 1 time in total.
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StevieG72
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Re: Home comfort mystery

Post by StevieG72 »

I have a heat pump that struggles to keep up when temps drop to the teens. I bought an oil filled radiant heater that works really well in warming up the area that I am occupying. I do not leave it on while sleeping or away from home, but it continues to put out heat for awhile after turned off. I will have it running on high for a few hours in the living room, then roll it in to my daughter’s room when she goes to bed. ( may run it for awhile in her room, but turn it off when I go to bed)

As far as your situation another poster may be on to something mentioning the humidity, 69 degrees could feel much different bases on humidity.
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TomatoTomahto
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Re: Home comfort mystery

Post by TomatoTomahto »

Sandtrap wrote: Fri Jan 15, 2021 7:35 am Presto Heat Dish (around $50 or less is a good price, the oscilating one that looks like it but is not a Presto or all metalic is not a good one).
Some Amazon sellers price gauge them. We've tried tons of different types and these are very rugged and put out and direct heat excellently.
(Amazon product link)
Good lord, at 1000 watts I hope it takes quite a bit of chill out of the air. I can heat 1500 square feet of my house at lower wattage via my geothermal! The below photo was taken with the temp at 28 degrees outside.

Image
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TomatoTomahto
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Re: Home comfort mystery

Post by TomatoTomahto »

Re ceiling fans, I run them the prescribed directions in the summer and the winter, but don’t really understand the difference. Either the cool air is drawn up the center of the room and the warm air comes down along the walls, or the cool air comes down the center of the room and the warm air goes up along the walls. Net net, I don’t quite see the difference, but I’m a good boy and do what the manufacturer recommends. :beer
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Sandtrap
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Re: Home comfort mystery

Post by Sandtrap »

TomatoTomahto wrote: Fri Jan 15, 2021 8:00 am
Sandtrap wrote: Fri Jan 15, 2021 7:35 am Presto Heat Dish (around $50 or less is a good price, the oscilating one that looks like it but is not a Presto or all metalic is not a good one).
Some Amazon sellers price gauge them. We've tried tons of different types and these are very rugged and put out and direct heat excellently.
(Amazon product link)
Good lord, at 1000 watts I hope it takes quite a bit of chill out of the air. I can heat 1500 square feet of my house at lower wattage via my geothermal! The below photo was taken with the temp at 28 degrees outside.
Yes. That would be the case for sure.
We use the heat dishes for when we are in a cold bathroom/shower or in the gym room (always colder there) or wherever we happen to be and we need to be warmed up a bit. Especialy if it gets down to single digits outside. Otherwise the house is on central heat so they are not needed. Our electric bill is very low so these occasional area uses don't seem to be impacting things.

For the OP: if he's in the kitchen in the morning making coffee and it's freezing right there, then the heat dish comes in handy to warm up while making coffee, the human, not the area. Like this.

j :D
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Arabesque
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Re: Home comfort mystery

Post by Arabesque »

Just wear layers, save money and the planet. Some things, like winter, require accommodation and acceptance.

The winter I spent in Juneau was snowy. The first time we shoveled the roof I complained, but by the second time, I had accepted it as a reality and was much happier (less miserable).
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Re: Home comfort mystery

Post by Jack FFR1846 »

Have you lost weight recently? I lost about 40 pounds and went from riding the chair lift at a ski area in 0 degree weather with my jacket open to feeling like my fingers are freezing in just 30 degree weather.

You say humidity is not a factor. Are you sure? Cold winter air will squeeze moisture out of the air. Put some humidifiers in the house. As a "do it now" thing, fill a pot with water and let it boil on the stove. That'll give you both some heat and some humidity. Of course check it and keep it full of water.
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lthenderson
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Re: Home comfort mystery

Post by lthenderson »

TomatoTomahto wrote: Fri Jan 15, 2021 8:05 am Re ceiling fans, I run them the prescribed directions in the summer and the winter, but don’t really understand the difference. Either the cool air is drawn up the center of the room and the warm air comes down along the walls, or the cool air comes down the center of the room and the warm air goes up along the walls. Net net, I don’t quite see the difference, but I’m a good boy and do what the manufacturer recommends. :beer
With the fan pulling up, I don't feel the breeze across my skin and stay more comfortable in the winter. In the summer, the fan is blowing down on me and that feels good when it is hot. I would agree there probably isn't much efficiency difference as long as it is running.
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Startled Cat
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Re: Home comfort mystery

Post by Startled Cat »

Jack FFR1846 wrote: Fri Jan 15, 2021 8:47 am Have you lost weight recently? I lost about 40 pounds and went from riding the chair lift at a ski area in 0 degree weather with my jacket open to feeling like my fingers are freezing in just 30 degree weather.

You say humidity is not a factor. Are you sure? Cold winter air will squeeze moisture out of the air. Put some humidifiers in the house. As a "do it now" thing, fill a pot with water and let it boil on the stove. That'll give you both some heat and some humidity. Of course check it and keep it full of water.
Weight loss is definitely a factor, but it doesn't explain why I'm so sensitive to the outdoor temperature.

Indoor humidity ranges from 55%-65% in the winter. When it's at the upper end of that range, I have issues with water condensing on the metallic window frames and dripping, so I definitely don't want more humidity. I actually run a dehumidifier in my bedroom to keep the condensation under control, and also for some extra heating (the dehumidifier is effectively a heat pump of sorts).
Arabesque wrote: Fri Jan 15, 2021 8:41 am Just wear layers, save money and the planet. Some things, like winter, require accommodation and acceptance.

The winter I spent in Juneau was snowy. The first time we shoveled the roof I complained, but by the second time, I had accepted it as a reality and was much happier (less miserable).
This is my overall philosophy and it's why I don't respond by turning up the thermostat even more. I'm mostly curious about the phenomenon I described and whether there are any tweaks that might improve comfort without throwing more energy into the space.
Sandtrap wrote: Fri Jan 15, 2021 7:35 am We have several Presto Reflective Heat Dish portable 110v plug in area/space heaters that have worked well to move around wherever we happen to be to take the "chill" out of the air. It's a simple solution that's worked in any home we've had over the many decades. Sometimes Costco has them for a good price. One of our Presto Heat Dish's is over 30 years old (also from Costco) and still works fine.
I could see this working very well for, say, a bathroom. Seems worth looking into.
LifeIsGood wrote: Fri Jan 15, 2021 5:36 am You mentioned having high ceilings. Heat rises. I'd be willing to be a lot of your heat is up there. If you have a ceiling fan(s) they usually have a reverse switch on them and will push air down from the ceiling rather than pull it up.
I've thought about installing a ceiling fan for summer, and wonder if it would be useful in the winter too. A ceiling fan might help force warmer air downwards, and mix air to prevent hot spots. It's not obvious to me how noticeable those effects would be.
serbeer wrote: Fri Jan 15, 2021 1:21 am Because your outside walls temperature is affected by outside weather. You warm body radiates heat to the colder walls losing it more rapidly on cold days even if thermometer in the room shows the same inside temperature.

Put your face close to the outside wall on colder day without touching it and you will feel the cold on your face as your body will radiate the heat at higher rate.

The fact that wall area is large, and especially that there are a lot of windows, which are always colder than walls not insulated as much, magnifies the effect. You can use inexpensive consumer infrared phone attachment, eg Seek Thermal, so see a thermal map of your loft, the windows will stand out quite a bit.

The heat radiation effect will be minimized if you sit at the center of the room, and rapidly accelerate as you approach cold walls.

In the summer, the effect will be reversed, the closer to the walls heated by sun you seat, the hotter you will feel, even in seemingly comfortable room.
This is really interesting and might be the explanation I'm looking for. In considering air temperature, I had been thinking about convection, but maybe radiative heat exchange is a big factor too.

I think there is a similar effect going on with the window condensation I mentioned above. I've noticed that it mainly happens on clear nights, and not on cloudy nights. The only conclusion that made sense to me so far is that the aluminum window frames radiate their heat into space, unless there is something in the way to reflect heat back towards them.

Looking at the loft in infrared is a great idea. I've been meaning to pick up an infrared thermometer for awhile, and this reply inspired me to finally order one. That said, it doesn't take any measurement equipment to know that the walls and windows get quite cold.
The Stone Wall
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Re: Home comfort mystery

Post by The Stone Wall »

serbeer wrote: Fri Jan 15, 2021 1:21 am Because your outside walls temperature is affected by outside weather. You warm body radiates heat to the colder walls losing it more rapidly on cold days even if thermometer in the room shows the same inside temperature.

Put your face close to the outside wall on colder day without touching it and you will feel the cold on your face as your body will radiate the heat at higher rate.

The fact that wall area is large, and especially that there are a lot of windows, which are always colder than walls not insulated as much, magnifies the effect. You can use inexpensive consumer infrared phone attachment, eg Seek Thermal, so see a thermal map of your loft, the windows will stand out quite a bit.

The heat radiation effect will be minimized if you sit at the center of the room, and rapidly accelerate as you approach cold walls.

In the summer, the effect will be reversed, the closer to the walls heated by sun you seat, the hotter you will feel, even in seemingly comfortable room.
+1 This is the correct answer. Anything warm to your touch is radiating energy towards you. Conversely, you will be radiating heat towards anything cool to your touch (causing you to feel cold). In the computation, those temperatures are raised to the power of 4, so, as the difference in temperature between the two surfaces increases, so does the radiated energy. (in a big way).
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TomatoTomahto
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Re: Home comfort mystery

Post by TomatoTomahto »

The Stone Wall wrote: Fri Jan 15, 2021 10:04 am Anything warm to your touch is radiating energy towards you. Conversely, you will be radiating heat towards anything cool to your touch (causing you to feel cold). In the computation, those temperatures are raised to the power of 4, so, as the difference in temperature between the two surfaces increases, so does the radiated energy. (in a big way).
As the recent owner of a stone house and surprised at stone’s non-intuitive thermal/insulating properties, I can’t help but chuckle at your user name. Thanks for the explanation.
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surfstar
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Re: Home comfort mystery

Post by surfstar »

Arabesque wrote: Fri Jan 15, 2021 8:41 am Just wear layers, save money and the planet. Some things, like winter, require accommodation and acceptance.

The winter I spent in Juneau was snowy. The first time we shoveled the roof I complained, but by the second time, I had accepted it as a reality and was much happier (less miserable).
This.
"Winter" here gives me an excuse to wear pants and an insulating layer inside! We've got all these great clothes for high Sierra camping and rarely get to use them at home. Not to mention the saving of resources and money!

Didn't turn on the furnace this morning, though, as it supposed to hit 85 today :o
illumination
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Re: Home comfort mystery

Post by illumination »

TomatoTomahto wrote: Fri Jan 15, 2021 8:00 am
Sandtrap wrote: Fri Jan 15, 2021 7:35 am Presto Heat Dish (around $50 or less is a good price, the oscilating one that looks like it but is not a Presto or all metalic is not a good one).
Some Amazon sellers price gauge them. We've tried tons of different types and these are very rugged and put out and direct heat excellently.
(Amazon product link)
Good lord, at 1000 watts I hope it takes quite a bit of chill out of the air. I can heat 1500 square feet of my house at lower wattage via my geothermal! The below photo was taken with the temp at 28 degrees outside.

Image
The 1000 watts would be on the highest setting, on the lower settings it cycles and uses less watts.

But it would also take all day of running a geothermal system to jump up the temp as quickly as a space heater does in a few minutes to get the small area you want warm. Not to mention what a geothermal system costs to install, I've heard some horror stories.

Space heaters are definitely not an efficient way to warm an entire home (maybe the worst) but so much of this psychological and it's more about just being near a radiant form of heat in a small area to feel comfortable. Someone working in a spot near a cold window and wants to "feel" warm for a few hours, it's going to be cheaper than cranking up the heat for the whole house to get that same effect. A space heater being used like 2-3 hours a day at 700 watts, my utilities that would be like an extra $8 month. Way cheaper than someone cranking up the whole house.

I've found the most efficient method is just wear warmer clothes and just get "used to it" but not every family member is on the same page. I'm an evil monster for saying the thermostat should never go above 69. :twisted:
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Re: Home comfort mystery

Post by bikechuck »

corysold wrote: Fri Jan 15, 2021 7:35 am Humidity matters as well.

69 feels different depending on the humidity of the air. Perhaps a humidifier could help in the colder months.
What is a good humidity level to shoot for in winter months if you live in an area where outdoor temps average in the 30's fahrenheit? Would that change if outdoor temps plunged to zero?
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Re: Home comfort mystery

Post by bloom2708 »

corysold wrote: Fri Jan 15, 2021 7:35 am Humidity matters as well.

69 feels different depending on the humidity of the air. Perhaps a humidifier could help in the colder months.
+1

Relative humidity of 60% at 69 feels much different than 30% at 69.

69 is on the low side for winter. 70-71 might feel more comfortable at the lower winter humidity levels.

Our humidity inside gets into the 20s% and that is with a humidifier attached to the furnace.
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TomatoTomahto
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Re: Home comfort mystery

Post by TomatoTomahto »

illumination wrote: Fri Jan 15, 2021 11:35 am I've found the most efficient method is just wear warmer clothes and just get "used to it" but not every family member is on the same page. I'm an evil monster for saying the thermostat should never go above 69.
69!! Are you Richard Nixon?? For those who don’t know, President Nixon is reputed to have cranked up the AC so that he could enjoy a fire in summer.

I discovered during my kids’ ice hockey practices that a pair of Merino wool socks went a long way to make me more comfortable standing there. You can always add clothes in winter, but removing too many in the summer will get the kids asking for my doctor’s phone number. We keep the house cold year round; what I save in the winter I spend in the summer.

Re geothermal, I was mostly teasing Sandtrap, which I don’t do often enough. :D Geothermal is a decades long investment.
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hvaclorax
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Re: Home comfort mystery

Post by hvaclorax »

In our home, we have a boiler powered by propane. Very even heat but early AM still a challenge to get warm. Ones body temperature is lower while sleeping then upon arising it also raise a little. This is when I feel cold. So some heat making activities are in order, including heated bathroom using space heater mentioned by others. Also, a nice hot shower or fire in fireplace. Even using the dishwasher generates some heat in the kitchen. Physical activities, horizontal or vertical are also very good. Dress for the temperature of the day. Leave the house for a walk or work in my shop, also carefully heated.
BTW, ceiling fans blowing down in the winter do feel cold. I think that’s why they should blow upwards to avoid the draft. HVAC
xkcd4711
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Re: Home comfort mystery

Post by xkcd4711 »

Air flow inside your space can also make a big difference, even if the temperature at the thermostat is the same.

For example, in Europe radiators are often placed underneath windows, which creates two separate loops of air: one of the window side (with a large temperature variation) and one on the room side (with a more modest temperature variation). With your wall-mounted gas heater, there may just be one big loop with a large temperature variation: air rising into your loft, cooling and descending along the outside wall (and windows) and returning to the heater intake with a rather cool flow close to the floor.

E.g. : https://blogs.sw.siemens.com/simulating ... mportant/

Something to explore with a thermometer (on a selfie-stick perhaps).

Not sure what that suggests as a remedy, though ... other than guiding the cold air flow around your feet.

V.
BeerTooth
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Re: Home comfort mystery

Post by BeerTooth »

most likely your body heat being lost via radiation to the cold windows. Try some thick fabric window drapes

radiation is the same reason mechanics can work comfortably in an un-heated shop, as long as they are near one of those glowing red gas radiant heaters, even though the air temperature is still freezing

there are three modes of heat transfer - convective, conductive, and radiative, however your thermostat can only sense and control static air temperature (convective)
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Re: Home comfort mystery

Post by MarkerFM »

The Stone Wall wrote: Fri Jan 15, 2021 10:04 am
serbeer wrote: Fri Jan 15, 2021 1:21 am Because your outside walls temperature is affected by outside weather. You warm body radiates heat to the colder walls losing it more rapidly on cold days even if thermometer in the room shows the same inside temperature.

Put your face close to the outside wall on colder day without touching it and you will feel the cold on your face as your body will radiate the heat at higher rate.

The fact that wall area is large, and especially that there are a lot of windows, which are always colder than walls not insulated as much, magnifies the effect. You can use inexpensive consumer infrared phone attachment, eg Seek Thermal, so see a thermal map of your loft, the windows will stand out quite a bit.

The heat radiation effect will be minimized if you sit at the center of the room, and rapidly accelerate as you approach cold walls.

In the summer, the effect will be reversed, the closer to the walls heated by sun you seat, the hotter you will feel, even in seemingly comfortable room.
+1 This is the correct answer. Anything warm to your touch is radiating energy towards you. Conversely, you will be radiating heat towards anything cool to your touch (causing you to feel cold). In the computation, those temperatures are raised to the power of 4, so, as the difference in temperature between the two surfaces increases, so does the radiated energy. (in a big way).
Another vote for this explanation. We have a summer house that we leave at 50 degrees in the winter. When we return in late spring, the outside temperature is still quite cool. Even after getting the interior temperature up to 69, it feels cold inside until the house and the things in it absorb the heat. Once that happens, and it can take several days, 69 feels warm.
adamthesmythe
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Re: Home comfort mystery

Post by adamthesmythe »

If you can afford it, set the temperature to what makes you comfortable. Forget the number.

If you can't, or don't want to spend the $- wear more. The biggest impact will be on the feet and head. Heavy or double socks, knit cap. You might not think it will make much difference but it does. Blanket on the legs or, better, those legging things.

I don't buy radiation. Yes, it goes like T^4 but it starts off really really small for objects at 98 F. I think you are experiencing convection cooling enhanced by drafts, even if not easily perceptible.
gretah
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Re: Home comfort mystery

Post by gretah »

I live just below the border with Canada so my area gets cold in winter.

Even though hydro-sourced electricity is cheap here, I don't want to be wasteful.

"Heat the body, not the room" is my motto.
I dress in layers.

Heating pads are my life in cold weather. During the day, I put them under my feet. If my feet are warm, I am usually comfy.

I have a couple in my bed at night.

I find heating pads last a few years. Electric blankets only last a year or so.
kevinf
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Re: Home comfort mystery

Post by kevinf »

LifeIsGood wrote: Fri Jan 15, 2021 5:36 am You mentioned having high ceilings. Heat rises. I'd be willing to be a lot of your heat is up there. If you have a ceiling fan(s) they usually have a reverse switch on them and will push air down from the ceiling rather than pull it up.
Sorry, but this is not good advice. Ever been into a very old cathedral with steam heat? Huge, cavernous room, the ceiling far above. And a few lonely radiators that keep everything nice and warm at ground level. Then some genius came in decades ago and overthought things... "doesn't heat rise?" he asked himself. "Isn't ALL the hot air up there?" even though it was nice and warm at the ground level as he pondered. "We need to install fans up there to bring the hot air down here!" And they did just that... and that toasty warm ground level became ice cold.

Hot air rises... then it cools down and sinks to be heat again and start the cycle over. It's cool LONG before it reaches the top, about 10 feet up is where it has imparted all of its heat to the thermal mass of the air. You are heating the ground level and you have a nice convection current creating an air curtain envelope of warmth that keeps the colder air up high from penetrating lower. If you install a blower up high, you break your air curtain apart and instead of just heating the bottom 10 feet... which those little radiators can do just fine... you must now heat ALL of the air in that cathedral. Suddenly those little radiators are massively overburdened and can no longer keep up.

Those fans you see that were installed decades ago aren't spinning, and for a good reason. That air movement will also draw heat from your body and make you feel colder.

As for FEELING cold... you feel coldness due to transfer of energy... not due to actual temperature. Touching 40°F wood feels much warmer than touching 40°F metal. They are EXACTLY the same temperature, but the metal conducts heat away from your skin much more efficiently and you feel it as coldness. A 60°sunny day feels warm due to radiant heat warming you, a 60° cloudy day feels cool due to you radiating your heat into the air. The poster that explained why the winter feels cooler than the summer nailed it... it's radiation and heat transfer.

What do you do about it? Insulation. You need to NOT be the most radiant body in the room. Put on a sweater. Aim a radiant heater at your workspace.
Last edited by kevinf on Fri Jan 15, 2021 10:03 pm, edited 2 times in total.
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rob
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Re: Home comfort mystery

Post by rob »

I have a large room (60x60) with high ceilings (25 feet) and one of the directional blowers makes a HUGE difference in winter... The heat clings to the roof.
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kevinf
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Re: Home comfort mystery

Post by kevinf »

rob wrote: Fri Jan 15, 2021 9:51 pm I have a large room (60x60) with high ceilings (25 feet)...the heat clings to the roof.
In this seminar at The General Society of Mechanics and Tradesmen of the City of New York, Dan Holohan delivers a talk that combines humor and practical technical advice about heating systems.

https://youtu.be/VR6u_71FKGU?list=LL&t=1977

I have cited my source.
Last edited by kevinf on Sat Jan 16, 2021 12:23 am, edited 1 time in total.
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Startled Cat
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Re: Home comfort mystery

Post by Startled Cat »

rob wrote: Fri Jan 15, 2021 9:51 pm I have a large room (60x60) with high ceilings (25 feet) and one of the directional blowers makes a HUGE difference in winter... The heat clings to the roof.
Is the idea to move air that would otherwise stay near the ceiling? Where do you point the blower?
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dziuniek
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Re: Home comfort mystery

Post by dziuniek »

That's why I think houses with radiators feel warmer, hmm.

I think the most comfy is when you have floor heating... My cousin has this is his bathroom and it's pretty darn awesome in the winter. No more stepping on cold tiles.
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Re: Home comfort mystery

Post by Quest80 »

dziuniek wrote: Fri Jan 15, 2021 10:52 pm That's why I think houses with radiators feel warmer, hmm.

I think the most comfy is when you have floor heating... My cousin has this is his bathroom and it's pretty darn awesome in the winter. No more stepping on cold tiles.
So true. We remodeled our large master bath a few years ago and added under-tile floor heating. Best thing we ever did.
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