# heat output from infrareds



## Doc (Jun 5, 2003)

Did a google search but didn't find what I needed (probably using the wrong terminology).

Curious to know the heat output of a 125w red infrared bulb vs 250w? Anyone know or how to calculate it?

Thanks.


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## Bearfootfarm (Jul 13, 2006)

The 250 should be about 850 BTU's

Infrared Bathroom Heat Lamp Only



> 1 - *250 watt* maximum, type R40 *bulb*, medium base, 850 *Btu*.


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## Doc (Jun 5, 2003)

Is it correct, then, to halved the Btus for 125w?


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## artificer (Feb 26, 2007)

There are 3.4btu/watt-hr of power. So, half the power, half the heat. 425 btu's for the 125watt bulb.

There are different ways to transmit heat. (conduction, convection, radiant energy) If you put a 150watt regular bulb in an insulated box, it will heat up the air in the box just as fast as the infrared light. If you want to dry paint on a car, keep chicks warm, etc., then the infrared light will directly heat whatever it shines on, without heating the air. 

Michael


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