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Bad trap or bad venting?

PChrisPChris Member Posts: 1
I have some radiators on what I believe is a two-pipe system that aren't having steam pass through them. The main vent is a Gorton #1. I'll take any help I can get.
Thank you


  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,133
    Check the outlet temperature from each radiator trap, while the boiler is firing. It should not be steam hot, or cold. You can order new trap insides, (Barnes&Jones), which makes it an easy fix.—NBC
  • KC_JonesKC_Jones Member Posts: 4,410
    I would suggest you don't have enough main venting, unless your house is the size of a shed.

    That said, if the traps are failed close they won't pass any air and that could cause them not to heat.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,133
    Or if one vent has failed open, it can flood the returns With steam, and close nearby traps, preventing steam from entering the radiators effected.
    KC is right about the main vent.—NBC
  • dopey27177dopey27177 Member Posts: 298
    Firstly the steam main needs to be insulated.
    Without insulation excess condensate can build up in the steam main.

    At the end of the steam main you need a steam trap to separate the the steam side of the system from the dry return.

    The purpose for this is to prevent steam from entering the dry return piping, If steam at pressure fills the return steam will flow up the radiator returns and close the radiator steam traps,

    The master air vent valve should be placed 6-12" away from where the dry return drops to floor (wet return to the boiler.

    This all I can tell you based on the info and pictures you posted.

    I hope this is helpful to you.

    Jacob Myron

    I wrote a book on steam heating (Steam the Perfect Fluid for Heating and some of the Problems)

    It is available at Dan's library, Barnes and Noble, Amazon and Dorrance Publishing, Pittsburgh Pa.

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