1890 Victorian house museum: sizing main vent

NealJ

Looking for help checking/sizing the vent at the end of the steam main. Original was a Dole 1933 with a 3/4” male inlet. I have 52’ of 3” pipe and 23’ of 4” pipe between the ‘original’ header and the end of the main where the vent is located. See attached sketch (sorry, I’m not a draftsman). Any recommendations are appreciated. Thanks!

Steamhead

That Dole vent is pathetically inadequate. It had to have been meant for venting an individual convector. Build a manifold of 3/4" pipe and tees, and install 5 Gorton #2 vents. Then watch how much better it works.

NealJ

Thanks so much for your input. I found ‘Balancing Steam Systems and how to use the vent capacity chart booklet on this site. I’ve turned the system pressure down to the .5 to 1.5 pressure range and I’ve ordered 3 Gorton #2’s to start (at over $100 each, I’ll take my time). I do all of this work on the museum and I volunteer my time, and I also donate all of my maintenance costs, so it adds up to a lot!