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Breakdown of CFA in one-pipe parallel system
Front: supply main with 133.5 attached rad; 31' of 11/2" and return main(steam filled to vents) 28.5' of 11/2" pipe=tot pipe CFA of .83, rads have 3.34 CFA.
Back: SM, 84sf of att rad,; 28' of 2" and return main 26.5' of 11/2" pipe=tot CFA .99, rads have 2.12 CFA.
Considering above, what would be proper main venting? Currently has MOM1 and G2 on front and 2 MOM1's on back.