tony17112acst wrote:Larry/Isayre

Please address my question with a coil electric heater with discretely limited BTU's and heat transfer before it goes up the stack. I thought it was a very good question. Please answer: " Will more heat transfer to the room by pointing a fan on the stove that contains this 50,000 BTU electric heater? "

That's a "yes" or "no" answer please.

Can the resistance of a resistor change if air (or a heat sink, or a water jacket, etc...) is applied to cool it? The answer to this is apparently yes. The magnitude and direction of the change are dependent upon the material involved. To quote Sting, it depends.

A few potentially helpful relationships are in order (pick the ones that suite you):

1 Watt = 1 Joule per second

Watts x 3.412= BTU/h

Watts = V*A

power P in watts (W) is equal to the energy E in joules (J), divided by the time period t in seconds (s):

P(W) = E(J) / t(s)

P = I x V

and also:

P = I^2 x R (Joules first law)

power P in watts (W) is equal to the energy E in joules (J), divided by the time period t in seconds (s):

P(W) = E(J) / t(s)

By definition a current of one ampere flowing through a wire with one ohm of resistance heats the wire at a rate of one watt, which by definition = 3.412 BTU's of heat.

2 amperes through the same wire would therefore heat it at a rate of 4 watts, or 13.65 BTU's.

If electrical resistance changes (and we have concluded that it can in a system where the resistive element is subject to cooling) then amperes (current is measured in these) must change also, since V = IR , whereby V is an implied constant here, so therefore the BTU's change as a consequence, as can be seen above.

But don't ever forget "system equilibrium" or that you can't have your cake and eat it too (the laws of thermodynamics).

In the end we are still talking in circles. I think I'll go out a buy an EdenPure heater now.