Message Board Thread - "Crazy temperature difference "

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Crazy temperature difference the darbster 4/3/2011
Can anybody suggest a reason for this distinct temperature difference. This is an interior wall on the second floor of a 2 storey building. There is a stairwell behind the first photo with masonry block wall. There is overhead radiant heating panels in the rooms.
I'm stumped.
Re:Crazy temperature difference-photo 2 the darbster 4/3/2011
here's the digital
Re:Crazy temperature difference the darbster 4/3/2011
here's the room on the other side
Re:Crazy temperature difference the darbster 4/3/2011
here's the IR of the other room
Re:Crazy temperature difference the darbster 4/3/2011
Here's a macro shot.
I'd really appreciate any feedback.
Re:Crazy temperature difference the darbster 4/3/2011
PS the red boxes in the elevation shot are the walls I'm referring to.

Re:Crazy temperature difference David Brown 4/4/2011

Have you tried checking the walls with a moisture meter?

Re:Crazy temperature difference IRJay 4/6/2011
Are these walls open into the ceiling? You may have a stack effect in these walls where the cooler dense air has settled in the wall structure. Moisture is an option but I would find that improbable as the material in the room is at the same radiance. Another option is that the walls had sound insulation installed and it has settled and has added to the mass of the lower section. These areas do not look actively heated which again can stratify the air in these rooms. I do not see radiant panels. I see air vents and return air grilles on the ceiling.
Re:Crazy temperature difference SW@Watn 4/6/2011
It would appear that even stand-alone material has a temperature gradient indicating a stratification as indicated by a previous reply.
I'm unable to tell by the pictures, but if this is the morning, perhaps the building heating system had only been recently turned on and is in the process of heating the building.

Re:Crazy temperature difference off19 4/6/2011
It is reflective radiant heat from the window inside the room. Upper portion is warmer exposure to sunlight. Try same picture at night and see if you get the dame result.
Re:Crazy temperature difference Glenn 4/6/2011
I agree with the radient heat theory. The level of the temperature difference seems to be about the same height as window.
Re:Crazy temperature difference Tanel 4/6/2011
This is like thermosiphone.
I see, that this building has been repaired. There are holes in the floor and maybe some window is open in first floor...
This is my opinion, greetings from Tallinn
Re:Crazy temperature difference dms 4/6/2011
From the exterior photo there appears to be a overhang area. Structural steel beams are most likely extending outward from the building envelope wall assemble. Structural& architectural plans and design would need to be reviewed this area. suspect a combination of cold air infiltration and cold beam transfer. Also building looks to be under construction or remodeling, they may have the RTU ventilation system shut off to prevent dust etc to the ductwork system. This cold be causing negative pressure in the building which would add to the cold air and cold beam transfer. With the RTU off this would also highlight the ceiling radiant heat panels as no air movement would be present to circulate the conditioned air. Did you happen to image the lower window sill area and a floor temperature reading.
Re:Crazy temperature difference tedinoue 4/6/2011
I'm dubious about all of these suggestions because of the last thermogram you show where you say "here's the IR of the other room."

Look closely at the image. Both the wall and the contents of the room show much colder, and consistently so. Why would rolls of material leaning against the wall as well as the hand truck in the middle of the room be affected by anything just changing the wall temperature. And if this is a room temperature gradient, I can't imagine it being so smooth.

And this is no small temperature difference so we're not looking at a subtle temperature gradient or a smooth change. Your going from around 65F to 75F at a precise location on the wall, maybe what, 40" above the floor?

Of course, I hate these non-smooth pseudocolor scales because they distort interpretation of the image. I'd much rather see a pure gray-scale image to see what's really going on in there.

Something just doesn't add up here!
Re:Crazy temperature difference fijidreamer 4/7/2011
Irrelevant to your initial question, but are you supposed to be wearing prescription or reading glasses? Digital images are both out of focus, the second is obviously worse. Maybe situational but I noticed and thought I would make another thermog share my pain! Best wishes!
Re:Crazy temperature difference RonColling 4/7/2011
Other questions to answer and consider:

What time were these taken? AM/PM
Are they running the heat all the time or only during certain hours?
It looks like it is still under construction, so they may not have the heat on the entire time, so this could be heating up or cooling down.
What are the outside temperatures. I'm assuming fairly cold, since snow is visable. That would also contribute to the colder floors.
Back to a really basic question - why were you there? What did they suspect or why were you called in to inspect?

Again, as others have said, I would rule out moisture intrusion due to the materials NOT touching the walls showing the same pattern as the wall. Also, water shouldn't wick up that far without an obvious event of rising water. The cooler temperatures are showing up higher on the (I assume) metal studs. That would lead me to believe that the concrete is cool and transferring temperatures up to the warmer materials (actually the other way around, but you know what I mean).

@ tedinoue - you can download the picture and change the pallet to greyscale. Right click - save pictures as - import it into your software and manipulate away. I didn't see anything different, but let us know what you find.
Actually, since I had it loaded, I saved it and will try to post.

I hope that helps,
Ron Colling, Jr.
Re:Crazy temperature difference the darbster 4/7/2011
I got the same pattern on two different occasions 4 days apart. Once in the middle of the night, once late afternoon.
Delta T was at least 20 Celsius, but these are interior walls.
It has to be stratification, but I've never seen anything this abrupt.
It's a new building being commisioned and I was doing a scan of the envelope. I submitted my report but haven't had an opportunity to investigate.
I will post again if I do.
Re:Crazy temperature difference Hill Top TI 4/8/2011
wow! Is this the first image taken that proves a thermocline can exsist in a atmosphere? I see this pattern all the time on my sonar while fishing. I would like to see the temperature readings you get from the lower level of the building.
Re:Crazy temperature difference dandersen 4/24/2011
#1 warm and cool air do not mix.
#2 This is air stratification of warm and cool air.

If you in fact have radiant panels in the ceiling, the radiant heaters heat the air more at closer distance from the heat source than at the floor. Not all of the radiant heat makes it to the floor. The air absorbs and re-emits heat in the process. Less dense air rises and cool are stays at the floor.

If you have a supply and return HVAC air duct system in the ceiling (forced air system) the hot air rises after discharge from the supply register. As the return is also located at the ceiling, it will not remove the cool air from the floor and it will stay there, cool.
Re:Crazy temperature difference dandersen 4/24/2011
Hill Top TI wrote:
this the first image taken that proves a thermocline can exsist in a atmosphere? I see this pattern all the time on my sonar while fishing. I would like to see the temperature readings you get from the lower level of the building.
This will not change between floors.
It is dependent upon the heating system design.

As for this condition being like your depth finder, air and water are both “fluids” and react the same.

Re:Crazy temperature difference 4/28/2011
this inage seems to me air stratification.

Re:Crazy temperature difference bdrogin 5/23/2011
The tell-tale clue is how the temperature differental carries across that rolled up piece of construction material - it has to be the air. Another indication is how it carries from exterior walls to interior walls so evenly. If it was sun through the windows, it would slant with sun angle.

I presume that when the building is completed and the HVAC system is turned on there will be more air movement and the stratification will not be as dramatic.
Re:Crazy temperature difference abenn 6/22/2011
As others have said it certainly looks like an air temp difference/stratification because the stuff not touching the wall shows the same effects, but I can't understand how the stratification can be so strong unless no one has been in the room for a long time. If the ceiling has radiant heating panels, could this just be reflected IR from those panels ?
If its stratification of air, then just turning on a pedestal fan for a short time should stir it up sufficiently to show this.

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