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Hot water boiler converted to steam, remaining return lines

piacas
piacas Member Posts: 1
My boiler was converted to a steam boiler before I bought the house. The old cool water retrun lines where cut and capped by the radiator. Can I just cap off at boiler before the relief valve and get rid of all the caps sticking out by the radiators? Is there any reason the old unused cold water return needs to stay capped at the radiators?

Comments

  • mattmia2
    mattmia2 Member Posts: 9,425
    Does it work properly? you should show us some pictures. I suspect someone bought the wrong boiler for a gravity hot water system and instead of converting the boiler or getting the right boiler tried to convert the system which almost certainly isn't going to work right unless they repipe the mains. You may have more work that you don't know about yet.
    EdTheHeaterManiOneCLamb
  • Steamhead
    Steamhead Member Posts: 16,726
    Sure it wasn't originally a 2-pipe steam system?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
    mattmia2EdTheHeaterManMad Dog_2
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,563
    Good luck with this one. I would love to see pictures of the boiler and how the pipes are connected to the radiators.

    Does it even work?
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
    mattmia2Mad Dog_2
  • Jamie Hall
    Jamie Hall Member Posts: 22,917
    oh dear
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    mattmia2EdTheHeaterManMad Dog_2
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,563
    piacas said:

    My boiler was converted to a steam boiler before I bought the house. The old cool water retrun lines where cut and capped by the radiator. Can I just cap off at boiler before the relief valve and get rid of all the caps sticking out by the radiators? Is there any reason the old unused cold water return needs to stay capped at the radiators?

    YEA.. in case you turn on the heat and it don't work this winter. Then you can put it back the way the old dead men designed it. Just sayin'
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
    Mad Dog_2mattmia2
  • Mad Dog_2
    Mad Dog_2 Member Posts: 6,713
    "Every Picture tells a story..dont it?"   Mad Dog 🐕 
  • Jamie Hall
    Jamie Hall Member Posts: 22,917
    Having recovered a bit...

    First, and most important right now, don't do ANYTHING to those return lines. You may find you need them rather badly.

    The next thing to do is to figure out whether the system was intended to be gravity hot water, which is quite likely, or steam, which is rather unlikely. That may take some real sleuthing, as it is very likely that just cutting and capping the returns was not the only hacking that was done.

    Having done that, the next thing to do is going to be figuring out which is the least expensive: restoring the system to the original likely gravity configuration, converting the whole thing properly to one pipe steam, or converting the whole thing properly to two pipe steam.

    This is not an amateur job, nor one for the local plumber. Where are you located? We know several folks in various locations along the east coast and somewhat inland whom I would consider qualified to study what was done and figure out the best way to go from here.

    But whatever -- don't do anything at all until we can figure out what you still have... and what was there before.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • jumper
    jumper Member Posts: 2,208
    Converting HHW to steam may work better than vice versa which I saw owners trying to do in the seventies. All about how well condensate returns.