Re: BTU's by the hour?

Adrian Arnold (arnold@bigb.win-uk.net)
Thu, 29 Feb 1996 22:55:36

Just for the record, according to my books, watts are a measure of
power and power per unit time is a measure of energy. Strictly
speaking, BTU (or BThU - British thermal units) are a measure of
heat or in other words, energy. They are, therefore, not strictly
comparable *but* if you run a 1.5kW heater for 1 hour, it will
generate approx. 5,200 BTU of heat as you so rightly say.

When you get to working out heat losses for installing central
heating, the books just say multiply the power output of the heater
in kW by 3412 to get the output in BTU, so.... I think your figures
look fine and would be interested to see your spread-sheet.

TIA,

Adrian Arnold.

>Someone will probably comment on one part of my math
yesterday where I >assumed that my electric heater's 5,200 BTU of
heat was an hourly unit. >
>In hind sight, after reading my message today, I'm not sure if I can treat
>it as an hourly unit. I have to find a better reference book and report
>back on that part. The calculation of BTU's in that volume of water looks
>fine though.
>
>See what happens when you go out on a limb and type as you think! I'll do
>my homework this weekend and get back with a short confirmation, or
>correction, on my new units of "1500-Watt-heater-Hours".
>
>"Da@# it Jim, I'm a Doctor, not a bricklayer!", (Dr.McCoy from StarTrek)
>
>Randy.
>
>