Rated output for electric radiant ceilings?
WEG
| Posted in Mechanicals on
I’ve been searching the web for a rule of thumb to calculate the rated output for a 40 year old electric radiant ceiling system. Must be some rule of thumb like 10 btu per suare foot……but I can’t find it.
Thanks
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Replies
I googled and a few sources give ranges of about 10-15w/sqft.
http://www.heattechproducts.com/12w-vs-15w-floor-heating-systems
http://www.transenergysystems.com/radiantvsconvection.html
http://www.nachi.org/forum/f18/radiant-ceiling-heat-18134/
Older ones might tend more towards the 15w number due to less insulation, but that is just a guess.
1 watt is 3.412btu/h, so these translate to 34 to 51btu/h per square foot.
Does it have any electrical specs on it, like amps or watts? If not, you could turn it on and count how much faster your electric meter runs to find out its electrical power draw. Then it's just the unit conversion that Nick provided from watts to BTU/h. And if you have amps, you can just multiply that by volts to get watts, since the power factor is 1.0 on an electric heater.