Welcome! Here are the website rules, as well as some tips for using this forum.
Manufacture recommended piping - one riser or two.
The recommended piping on a CAC-BDP BS2A boiler, shows using 1 riser or 2 risers, but does not explain what should govern the choice of either one. The 2 riser example shows 2 1/2" riser and 2 1/2" horizontal. Where does the wet and dry steam separate? I am considering making the horizontal a 3" with a 3" rise to the main with a reducing ell to the main steam line (one pipe, parallel flow) 2 1/2". It should also be noted the 2 1/2" main runs about 6 feet, then splits off to 2 mains, one remains 2 1/2" and the other is 2". Both returns are 2" drops at the boiler. This boilers existing piping arrangement is fu-bared, and I am going to re-pipe it. Should I brake away from the recommended piping, or follow it? Also, what in the world determines 1 riser or 2 risers, when the manufacture leaves that choice to the installer? with no numbers to help the installer make a choice. The other thing I found strange, the Hartford loop into the equalizer is shown to tie-in 6" below the water line, not 2". What-up with that? This is a 187500 BTU residential boiler. The attachment is the 2 riser drawing.