Surface temperature of new LowE window

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Surface temperature of new LowE window

#1 Post by ToddJ7 » Mon Aug 06, 2012 6:10 pm

I recently had a single window replaced with LowE 366 glass. After installation I am surprised at the significant surface temperature difference between the LowE366 and the non-LowE glass window adjacent to it ... but not in the way I was expecting ...

The LowE window glass temperature (in the center) on the INSIDE is ~20deg WARMER then the temperature of the older adjacent non-LowE window (both are illuminated the same amount by the sun). Note that I am in Chicago where the temperature has been in the mid 90s and I keep the house temp around 77 ... clearly I am getting a significant heat transfer through this window and is therefore doing a poor job of insulating me from the outside.

What is going on here ... this is particularly counter-intuitive. Is there 'directionality' to the installation where the module could have been installed backwards?

Any insight is appreciated.

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Windows on Washington
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Re: Surface temperature of new LowE window

#2 Post by Windows on Washington » Tue Aug 07, 2012 12:23 am

This is a very likely scenario.

The Low-e coating on the glass is reflecting more of the sun's energy (as compared to letting it penetrate) so it may cause a slight increase in surface temperature.

If the Low-e is on surface 3 (i.e. the interior surface of the inner pane), it is probable.

If the Low-e were on surface 2, the temperature difference would be less notable.

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