Possible to Calculate BTUs from Surface Temperature
stevedavis
| Posted in General Questions on
Basic theory question. I have an IR camera. Is it possible to calculate BTU gains and losses based on surface temperature?
For example, if I have a wall that IR camera is saying is 80F. And I have a room that’s air temperature is 70F. Is it possible to calculate the conductive heat gain?
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Replies
I don’t think is as simple as you are hoping. The volume of air flowing across the wall would be a huge unknowable factor.
Walta
Is 80F the interior or exterior temperature of the wall?
In this hypothetical scenario, it would be the interior temperature of the wall.
The rule of thumb used for radiant heat design is that a floor delivers 2 BTU/SF for every degree in temperature difference, and a ceiling delivers 0.71. (These are from John Siegenthaler's articles).
A wall would be somewhere in between.
If this was electronics Ohms law calculation test question and BTUs = Watts, Temp = Volts, Air flow = Current. We only know one of the three variables it is impossible to answer because two are required before you can calculate the third.
Walta