"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Doctor Drivel wrote:

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Doctor Drivel wrote:


11C Temperature Difference Between Flow and Return
(81C flow - 70C return)

Pipe Size (mm) - approx kW/hour

15 - 6.0
22 - 13.4
28 - 22.5

What the hell's a kilowatt per hour? [Bearing in mind that a
kilowatt in its own right is a measure of energy consumed/delivered
per unit time]

BTU/hr & kW = power

Correct

kW/hr & BTU = energy


WRONG!

It is?

Well, actually, BTU is energy

So, it's not wrong.

but kW/hr isn't. kW-hr would be - but
that's different because it's power *multipled* by time rather than
*divided* by time.

But even if you (incorrectly!) believe kW/hr to be a measure of energy,

It is because we buy out electrical energy using that.

your
pipe capacity heading is *still* wrong! A given size of pipe will deliver
a
certain amount of energy *per unit time* - in other words, a certain
amount
of *power*. So your units need to be kW - *not* kW/hr or even kW-hr.

[And yes, I *do* have a degree in Physics]

Get your money back.