Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Steam Main Air Vent Size?


I am renovating an old house. Much of the old heating system was destroyed.

I have a parallel flow system with 2 mains. Each main is 2.5" pipe. One main is 18' long. The other main is 37.5' long. I put in two hoffman 75 main vent valves a friend lent me to test the system. What is the correct size valve for each vent?

Any help would be appreciated.

Thanks and regards,


This discussion has been closed.