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old vacuum system - need help identifying

Hi Guys -
This looks like an old vacuum system. Can anyone identify it? Just want to know a little more about it before I change any radiators.


  • Steamhead
    Steamhead Member Posts: 16,728
    Probably a Paul system or similar. Is there a name on the air vent?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • mattmia2
    mattmia2 Member Posts: 9,455
    Is that vacuum vent line lead?
  • Steve_210
    Steve_210 Member Posts: 645
    Cannot see any markings on the air vent,
    Pipe is black steel not lead thanks
  • Steve_210
    Steve_210 Member Posts: 645
    Just install a one pipe radiator seems to work fine
  • dopey27177
    dopey27177 Member Posts: 887
    Old one pipe vacuum systems were used on coal fired systems. with the advent of oil and gs fired boilers the systems did not work right. The best you can do is to replace any and all vacuum type air vents and replace them with Hoffman #40 vent valves.

    Additionally, Replace the main vent on the steam main with a Gorton # 1 or a Gorton D vent valve. Both are high capacity vent valve. The difference is the shape and physical size of the valves.
    This will leave you with a simple one pipe steam system.

    Set the steam pressure to no more than 3 PSI off and 1Psi ack on.

  • Steve_210
    Steve_210 Member Posts: 645
    Thank you it’s an apartment building cannot mess with the boiler but thanks for your help