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.

Main vent location




  • rich on heat
    rich on heat Member Posts: 47
    Main vent location

    I have a 1 pipe steam system. Last year, I have a plumber installed
  • rich on heat
    rich on heat Member Posts: 47
    Main vent location

    I have a 1 pipe steam system. There was no main air vent installed, I think it was plugged. Last year, I have a plumber installed a Gorton 1 main air vent where it was plugged:

    If you look at this pic:
    This is the end of the main pipe and then curve to the left to a raditor and then pic 1. Those are 3 risers that feed 2 raditors in the first floor and 4 in the second floor.

    My question is, by having the main air vent there at the return, does it serve any purpose? I haven't really noticed. Also, will adding another Gorton 1 with a tee there will help? I have a water hammer problem in my master bedroom. Air vent is changed, radiator is pitched. Also, my bathroom vent and third bedroom hisses loudly. I did some skimming of the boiler but probably still need a more thorough skimming. It's much better than when I bought the house last year thought.

  • Jian-
    For some reason your pictures aren't available at the moment. (the site times out) You can load them here on the Post Message form by using the Attachment button at the bottom of the form.
    If you don't have them already I would get Dan's books (See a "Steamy Deal" at the bottom of this page) They're easy reading and are packed with information and trouble shooting tips on steam heating. They really helped me straighten my one pipe system out. I would say that they are a "must" for anyone with a steam heating system.

    Generally you should have a vent near the end of your steam main(s)to allow the air to escape. Most people use a Gorton # 2 for this which I'm told has 3 times more venting than a Gorton #1. On your bedroom radiator you might want to check the slope with a bubble level. I thought one of mine looked okay but it was actually sloping in the wrong direction. My hose is old and had sagged a little. Also make sure the valve on the inlet of the radiator is fully open. These valves operate either fully open or fully shut. When does the water hammer take place? At the beginning, middle or end of the heating cycle?
  • ataching pics


    I have Dan's book. As I stated, radiator is pitched correctly, valve is fully open.Loud bang is at then end of heating cycle.

  • I did read where you checked the radiator slope. Only reason I mentioned it is that I initially checked the slope of my radiators by shimming up the end opposite to intake and measured from the the floor rather than using a bubble level. Took me a long time to figure out one of them was still sloped the wrong way due to my house settling.
    Your pictures came though fine. You might also want to post pictures of your boiler piping, especially the return.

    From the pictures,your vent placement seems very different from mine and I, as an amateur, am only an "expert" on systems that look exactly like mine and so, like you, I'd be interested in what the pros have to say.
    Just as a thought-have you checked your mains and returns for proper slope (no sags in the piping)? This was a problem I found in my steam system.
  • Jian_2
    Jian_2 Member Posts: 1

    I have a 24" level and I checked it from left to right. It's properly pitched, no sag. The main and return looks good too.

    Anybody with anymore ideas?
  • Help?

    Any more help would be appreciated.
  • Bill_110
    Bill_110 Member Posts: 52

    The vents on my mains are near the boiler on the ends of the returns before they dip down towards the boiler to become wet returns. I have no idea whether this is the proper location but they've been there a long time. I know that after a while you can hear them hissing. Does your Gorton vent give any indication of venting air by making noise, can you feel anything coming out? Does the tee it's on get hot? I don't know much about the subject, but if your vent isn't actually venting it isn't doing any good.
  • vent help

    when i was experimenting with my vents, i put them in series with a ball valve. that way i could remove them [valve off] while steaming to check for the rush of air, and the arrival of steam, without danger.
    some parts of the pictures of your system make me think it may be a modified vapor system which used to operate on a couple of ounces of pressure. some even had no vents-just an open pipe.other systems had orifices to allow only the amount of steam in which could be condensed in the radiator.
    if you were in baltimore you could consult professor steamhead who knows all these vapor systems very well.
    at any rate check and see if the removal of the main vent speeds up the delivery of steam but be careful as those burns are very serious!-nbc
  • Jian
    Jian Member Posts: 12

    It's a Weil McLain EG45 boiler if anyone wants to know. I think the main air vent is working because in the past, I have heard a small hiss from it. It's hot to the touch too. When I have the main vent installed last year, I did not noticed any speed up in the steam delivery compare to without it. So, doubt removing it will be any different.

    My house is 18 x 35'. This is what I know of the piping. The main pipe is 4' above the top of the boiler. There is about 6' of pipe before it turn 90 degree back to the house. That distance is about 32'. At the end, are 3 risers to the first and second floor. Then turn 90 degree about 6'. In between is a radiator. Finally, turn 90 degree is the main air vent. The pipe is a few inches lower after the turn. It will extend for about 7' and then drop to the floor level. From there, it's about 25' back to the boiler.

    Since it's cold the past couple of days in NYC, my boiler took about 70 minutes to move 7 degrees from 60 - 67. Outside temp is around 35 with wind chill of mid 20. After the boiler is running for about 20-25 minutes, it would stop. Once the pressure drop back down, it will fire for several minutes and then stop again for a minute once it reach 2.5 psi. This will repeat until the set temp is met. Is this normal? I have the stat set to 2 cph.
  • Jian
    Jian Member Posts: 12
    Minimum header distance from waterline

    OK, I posted in another forum. Someone pointed out that my waterline to the header does not meet the Weil McLain 24" minimum requirement. From my measurement, it's 17". Also, there are 2 risers coming from the boiler. Instead of the main riser coming off the end of the header, it's in between the 2 risers. So, these 2 problems are probably causing the issues I am having.

    Any rough estimate what it would cost for someone to repipe it?

    Here are the updated pics of the setup
  • first of all

    Your near boiler pipings is installed wrong.... get the boiler installation manual and you'll see why
  • bob young
    bob young Member Posts: 2,177
    the wrong way

    That heel tee connecting the equalizer is a major issue. believe it or not 90 % of the boilers i have seen in bklyn are piped with the supply inbetween the riser take offs. and most work fairly satisfactory. and those are the good piping jobs. go figure. never met a new york plumber yet that ever heard of a drop header.
  • drop header

    Just curious, is the drop header really needed if I get someone to repipe the header above the 24" minimum and move the supply to the end of the risers?

    And can someone please just provide a very rough estimate for the cost so I know what I am dealing with?

  • Jim_171
    Jim_171 Member Posts: 2

    Jain homeowner here who repiped his boiler. From the photo repipe is straight forth . Attach new twin supply risers from boiler of proper lenght.Pipe the supplies together and and then pick up the single takeoff to the main then down to the egualizer. You have a bullhead tee( takeoff is between the supplies).This sends steam hitting steam head on that creates problems. If piped properly it will look similar to what you have but it will be higher and the two boiler supplies will be will be piped together before the takeoff to the main. Good Luck Jim
  • don't have the tools


    I understand what need to be done but 1) I don't have the tools for pipe this big 2) I am a small guy, not sure I can get these pipes loose if I have the tools. LOL 3) I feel better (not wallet-wise though) if a pro did the job.
  • Jim_171
    Jim_171 Member Posts: 2

    By all means use a Pro he can repipe that fairly quickly.With any luck he my be able to use some of the existing fittings to keep cost down.
  • Kara
    Kara Member Posts: 36

    The following might be of help to you.

    Here's a link to picture of a good dropheader that was done by Boilerpro

    http://forums.invision.net/Attachment.cfm?Martin New Steamer 005sm.jpg&CFApp=2&Attachment_ID=35977

    This picture and your installation manual should give you a pretty good idea of what you need.
    Note: The header needs to be pitched towards the equalizer.
    The equalizer (per Dan's instructions) should be no less than 1 1/2 inch pipe. The elbow at the end of the equalizer
    should be the same size as the header and point straight down before it is reduced.
    You might also want to look at Gerry Gill's site for ideas.



    I'm not sure what exactly the rules are, but it is my understanding that discussing prices on this site is not proper "form" so I doubt if you'll get an answer on this.

    Since you have Dan's books(and with the photos from the sites listed above)you should be able to sketch out the setup you want and, with the following supply sites, price it out so you'll have a pretty good idea of the material cost and with a diagram it should be easy to get a
    bid for the labor to do the installation.

    For pricing: (use Cast Iron fittings)

    State Supply


    Plumbers Supply


    McMaster Carr

This discussion has been closed.