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Adding Radiator

We are constructing a one room addition and will be adding a radiator to the existing two pipe system. I have posted some topics relative to this addition in the past and now the day is finally here for piping. There is a supply and return branch already tapped into the existing main and return that we will be piping from. The plumber is using VIEGA - 1 inch supply and 3/4 inch return. The location of radiator will be towards the end of one of the mains.

Other than making sure lines are pitched properly and they dont become low point in system should I have a tee with threaded plug installed in the return line in case I need to add a vent? My main vent is a gorton no.2 at boiler (just installed - will be first run this season). With the viega I will not be able add anything later on my own so that is why I ask if I should plan ahead with the threaded tee. Should it be close to the trap outlet or back towards the return main?



  • KC_JonesKC_Jones Posts: 4,097Member
    Isn't this a steam system? That is supposed to be piped with black pipe and fittings.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • GBartGBart Posts: 753Member
    KC_Jones said:

    Isn't this a steam system? That is supposed to be piped with black pipe and fittings.

    Viega makes pro press fittings for steam. That could be what they mean.
  • JUGHNEJUGHNE Posts: 5,580Member
    I would put a tee on both the supply and return.
    I have been venting the supply mains on 2 pipe systems that are pumped returns and the steam delivery has increased...….some may frown upon this but it works.

    Without know the overall length of your system, a steam supply vent at that point may not improve the system.

    But tees are cheap at this point and plugs are even cheaper.
  • josephcjosephc Posts: 35Member
    edited October 2018
    the viega is black pipe; I have posted questions on that option in the past - I also confirmed with the mfg that its not an issue with low pressure steam. What it does do is not give me many options if I have to add something myself later.
  • FredFred Posts: 7,815Member
    Tee's and plugs at the end of a steam supply and Tees and plugs/ full port valves on returns are never a bad idea
  • JUGHNEJUGHNE Posts: 5,580Member
    The plumber could add black pipe threaded tees/nipples at the takeoff point, then go with his press system.
  • josephcjosephc Posts: 35Member
    If I need to add venting later is it better to have the tees located closer to the radiator (before the piping goes up through or down through the floor) or should they be where the new return and supply tie into the main and dry return?
  • JUGHNEJUGHNE Posts: 5,580Member
    Usually you would vent the steam main and maybe the dry returns. Depends upon the piping plan of the whole system
    There would usually be more clearance at the main pipes. IMO
  • Some 2-pipe systems have crossover traps piped from main to return, in conjunction with an ancient “air eliminator”,which acts as a main vent.
    If you don’t have that configuration, then put regular main vents, such as “Big Mouths” on the end of the returns.—NBC
  • josephcjosephc Posts: 35Member
    my system is a 2 pipe gravity system with crossover traps at the ends of the two mains. There is a single vent at the dry return near the boiler. closest system that it resembles in the art if steam is the dunham systems with mine missing the return trap or air eliminator.
    I may start a new thread regarding venting of the system.
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