btu's of the zone divided by 500 x delta tee ( that gives your g.p.m. ) then to get your head pressure you take the total length of pipe (longest zone) then you multiply by 1.5 elbows and other fitti… (View Post)
first we need pictures of how its set up. if this helps you can install a taco 4900 air eliminator of the indirect water copper to get the air out of THAT LINE ONLY. (View Post)