On Sat 16 Feb 2008 23:08:42, Donna Ohl, Grady Volunteer Coordinator
wrote:

On Sat, 16 Feb 2008 22:57:32 GMT, Donna Ohl, Grady Volunteer
Coordinator wrote:
I would guess any engineer should be able to tell us what this
41,045 magic number really is.

I'm surprised a chemist or engineer isn't on this group.

I think this is the fundamental answer!

page 11, Water Heating Calculations
http://www.green-trust.org/2000/solar/solar.pdf
43,302 kJ/day is 41,045 Btu/day is the energy delivered to the hot
water load per day

And, this one says most plumbers don't understand the efficiency
factor for home water heaters

Residential Gas Water Heating:
Program Design & Specification Considerations, page 6
http://www.cee1.org/cee/mtg/09-07ppt...20Residential%
20%20Gas%20water%20heating.ppt
Annual Savings (Therms/year) is based on
the DOE Test Procedu (41,045 Btu/EF*365)/100,000


Boing!! Payoff.

You tell 'em Donna. Show them you knew the answer all along.

Poor " and others like him now don't know what's
hit them.

Nothing like reeling in a very long fishing line that you've
carefully laid out. Good one!!