Please proof this new article about double-paned windows. John McKenna mentioned.

[Nick Gromicko]

http://www.nachi.org/condensation-do...ed-windows.htm

[Jason Kaylor]

Nick,

You might wanna grab one of the many IR images around of a gas filled window where the seal has failed. It makes a very distinct bullet pattern in the middle of the glass with an infrared camera. When the seal goes it sucks the two panes of the window together. Providing there is a Delta T there will be a temp difference from the outter edge of the window to the middle.

Just thought it might be a good image for your article.

Jason Kaylor – JJ
VP of Sales
877/207-1244
AC Tool Supply
Fluke Thermal Imagers
Testo Infrared Cameras
HotShot Hi-Rez Infrared Cameras
Fluke TiR1 Resources
FLIR B60 Resources
Retrotec Duct & Blower Door
Kansas City KS Infrared Inspections

[John McKenna]

Nice image...

[John Snell]

Originally Posted by jkaylor

Nick,

You might wanna grab one of the many IR images around of a gas filled window where the seal has failed. It makes a very distinct bullet pattern in the middle of the glass with an infrared camera. When the seal goes it sucks the two panes of the window together. Providing there is a Delta T there will be a temp difference from the outter edge of the window to the middle.

Just thought it might be a good image for your article.

Jason Kaylor – JJ
VP of Sales
877/207-1244
AC Tool Supply
Fluke Thermal Imagers
Testo Infrared Cameras
HotShot Hi-Rez Infrared Cameras
Fluke TiR1 Resources
FLIR B60 Resources
Retrotec Duct & Blower Door
Kansas City KS Infrared Inspections

This is not exactly the case! Windows can, of course, lose their seal and you will then find moisture between the panes.

For argon filled window units, however, the issue is actually the result of pressure equalization between the high concentration in the window and the lower concentration in the atmosphere: they want to equalize and will if at all possible. Over time, argon escapes, even through a "normal " seal or window and the panes collapse; if the window is smaller than about 20"x20" it will often implode! Larger windows simply flex but will, ultimately, end up touching each other. You can see this with IR long before you can see the condensation (which occurs on the exterior of the panes). I'll attach in next posting.

My partner, Rob Spring, PE, and I authored a paper, A Unique Thermal Problem Found in Certain Double-Glazed Windows, a number of years ago on this. Along with many others, it is available as a free download (we only ask for your contact information) at our website:
http://www.thesnellgroup.com/WhitePapers.aspx.

This is a great find, especially before they go out of warranty!!!

Thermally yours,

John Snell
ASNT NDT Thermal/Infrared Level III #48166
Snell Infrared
800-636-9820
802-229-9820
http://www.thesnellgroup.com
http://www.IRTalk.com
http://www.learnnewsolutions.com/