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What could cause this to happen

Mark_72Mark_72 Member Posts: 30
Pressure in return on boiler start up. vacuum system. water pushing up in the return's
? Anybody.
MJS Service's Inc.


  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,138
    What are we looking at in those pictures?--NBC
  • Mark_72Mark_72 Member Posts: 30
    Steam trap on rad . I tried to put up video but was not able to post. water is shooting up in the returns and causing problems. I have never seen this happen . Vacuum system in an apt building. happening throughout the building . building is 13 stories and a down feed system.
    MJS Service's Inc.
  • AlCorelliNYAlCorelliNY Member Posts: 63
    is it double trapped?
    Al Corelli

  • Mark_72Mark_72 Member Posts: 30
    No double trap. two pipe system
    MJS Service's Inc.
  • AbracadabraAbracadabra Member Posts: 1,948
    Mark said:

    Pressure in return on boiler start up. vacuum system. water pushing up in the return's
    ? Anybody.

    Please provide pics of near boiler piping.

  • SteamheadSteamhead Member Posts: 13,864
    Is the vac pump running when this happens?
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,088
    Is the overflow and vent on the tank plugged or capped.? Are the returns hot, do you have traps blowing through? Any wet returns or lifts in the vacuum system? Is the vacuum pump pulling a vacuum?
  • Mark_72Mark_72 Member Posts: 30
    This happens when the vac pumps are running. The pumps are venting but I have not ruled them out. Steamhead you were in this building apox. 2006. It's a Shipco pump /boiler feed system.
    I am getting some hg 1/2at start and then I've seen it pull as much as 10hg. I just have not been able to take system down to rebuild vac just yet . that is in my plan as soon as we shut down for the season.
    MJS Service's Inc.
  • Mark_72Mark_72 Member Posts: 30
    I'll post some pic's tomorrow
    MJS Service's Inc.
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