Banging pipes and venting mains

raemac

I have 2 gorton #2 vents on end of 100 ft mains. The seem to open when cold but close when hot even when no steam comes through. This is causing no ventilation for water to flow back into boiler and get stuck in pipes. My installer of new system separated first floor from 2nd and 3rd floor with electric valves that they use in commercial installations. Lots of banging in pipes. My first question is about set up. Does this look correct? Am a I asking for trouble having 2 zones? Should I have more vents in main at different locations?

Steamhead

Is this

a one-pipe or two-pipe system?

JStar

Steam

Hard to see but it looks like the near-boiler piping is all wrong. Is the banging coming from around the boiler?



Zone valves can be installed with no problems, but they need some special attention.

raemac

One pipe but two mains

It is a one pipe system with 2 mains. It used to be 2 separate systems in a two family home that is now a one family home.

Jamie Hall

If those zone valves

are not dripped on both sides into wet returns, you will have trouble with them.  They will hammer -- it's almost guaranteed.  Further, if they are not full port valves, you will have even more trouble, as steam will have trouble getting past them (the thermodynamics is messy, but the bottom line is that saturated steam condenses like mad when it goes through a restriction which then opens out again).



As Joe said, zone valves can be done on one pipe steam -- but it is a little tricky.



The Gortons should close when steam hits them.  That's what they are meant to do.  They will open when they cool a little; that's also correct.  They will NOT open, however, if the pressure is too high, so that's something to check.  I doubt very much, however, if a closed vent would prevent condensate from draining back.  You are not dealing with a full pipe here; the condensate is laying on the bottom, and there is ample opportunity for it to drain back and for air in the pipe -- vent open or not -- to replace it.



On additional vents.  Depends a little on where vents are in relation to those zone valves.  If there are vents beyond the zone valves, they need to be duplicated on the hot side of the valves.

raemac

Zone valves

Thanks Jamie,

I think the zone valves could be the issue.

I may have to have someone come out to take a look at configuration

Double D

Lots to consider when using zones on Steam Heat

The system has motorized valves.

http://www.heatinghelp.com/article/95/Problems-that-plague-ALL-steam-heating-systems/80/Theres-water-hammer-in-the-system

The gravity-return system has motorized valves.

http://www.heatinghelp.com/article/95/Problems-that-plague-ALL-steam-heating-systems/90/The-boiler-is-flooded

There are motorized zones valves near the header.

http://www.heatinghelp.com/article/95/Problems-that-plague-ALL-steam-heating-systems/96/The-condensate-or-boiler-feed-pump-doesnt-behave-as-it-should

Zoning steam systems.

http://www.heatinghelp.com/article/326/Zoning/253/Zoning-Steam-Systems

Zoning a steam system? Watch out!

http://www.heat-timer.com/enFiles/News/newsletter6_20100408085351.pdf