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New to steam heat.


I have two weil mcclain boilers and need advice, do I leave the two control knobs open (between the glass water gauge)?  One of the boiler's is giving me trouble having to manually add water but I think It was because the two knobs were closed. Please advise.  Thanks!



  • Pumpguy
    Pumpguy Member Posts: 654
    edited January 2022
    Yes, you need the top and bottom shut off valves on the gauge glass assembly open to see the water level in the boiler.

    Only close them when you want to drain the water column in the glass, or when you wish to change or clean the glass or their compression grommets.
    Dennis Pataki. Former Service Manager and Heating Pump Product Manager for Nash Engineering Company. Phone: 1-888 853 9963
    Website: www.nashjenningspumps.com

    The first step in solving any problem is TO IDENTIFY THE PROBLEM.
  • Jamie Hall
    Jamie Hall Member Posts: 23,273
    Those knobs must be open. When you look at the gauge glass, ideally the water level should be visible somewhere in the middle third or so of the glass, but it can be a little higher or lower -- so long as you can see it.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England