Adding main vent to steam zone

Markvia55

hi all- I am trying to figure out if my proposed location for a main steam vent is acceptable- my steam zone has no main vent and is quite noisy. The radiators have individual vents that I am working on replacing as they are old. I have a 1 pipe steam system with a parallel return. I purchased a Gorton #2 and plan to T off the small horizontal 1 1/4 pipe shown before the drop to the boiler. I’m also attaching a pic of the rest of the main

Thanks in advance

Jamie Hall

By "noisy", what do you mean? Steam should be silent, or very nearly so. Are you referring to banging and knocking? Tick tick sounds? What?

A new main vent is unlikely to make much difference in noise…

mattmia2

you can do it near the end of the main too. if you do it at the boiler the whole return will heat which is ok but a bit less efficient.

Markvia55

https://forum.heatinghelp.com/discussion/comment/1888760#Comment_1888760

banging and knocking

mattmia2

banging and knocking is more likely boiler water quality or near boiler piping.

mattmia2

or possibly pitch of the runouts to the radiators or broken radiator valves or a radiator valve that isn't fully open or closed.

Jamie Hall

Banging and knocking is almost always water hammer (rarely expansion — that's gentler). And water hammer is always water pooling where it shouldn't be, or failing to drain properly.

Venting problems have little or nothing to do with it.

BUT

Pipe pitch and possibly partly closed or failed supply valves most assuredly do. If you can locate the noise to one particular pipe or radiator that tells you where to begin looking at least. The most common problem is a pipe which has inadequate pitch to drain, allowing water to pool; somewhere between a quarter inch per foot and half an inch per foot is a real minimum, and the pipe must drain towards the boiler or a drip to a wet (floor level) return. Sags can be a villain — not only the end to end pitch of the pipe but the pipe must be straight.

So… a real quicky is to start with making certain all the service valves on all the radiators are fully open. Then go into the basement and make sure that all the pipes have decent pitch.