Great hydronic heating system explanation here.

Best explanation of how hot water heating works is right here on this PDF by Bell and Gossett.

They walk you through it all.
http://www.bellgossett.com/BG-Literature-Detail.asp?LiteratureID=1195

Nothing There Bob

Hmmm I pasted it from the other thread here.Re doing.

Fixed…http://www.bellgossett.com/BG-Literature-Detail.asp?LiteratureID=1195
(guess copy only does it graphically here.)

http://www.bellgossett.com/BG-Literature-Detail.asp?LiteratureID=1195

http://www.bellgossett.com/BG-Literature-Detail.asp?LiteratureID=1195

Shoot… I misread the title. I was looking for something on Hydroponics.

Jeff