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Water capacity for Dunkirk PSB-7D 225,000 Btu steam boiler

I am trying to determine the water line capacity of the Dunkirk PSB-7D 225,000 Btu boiler. I have already called Dunkirk and got the wrong information. Any suggestions?


    JUGHNE Member Posts: 11,021
    Fill it and then drain into buckets for measurement.

    But if you drain it down to the LWCO that would show what is available for making steam before shut down.
  • Greg_44
    Greg_44 Member Posts: 5
    I could do that. I was hoping there was a chart or something like that.
  • Jamie Hall
    Jamie Hall Member Posts: 22,912
    It is likely that the volume of water per inch of drawdown is variable, since it will depend on the interior geometry of the boiler. Not knowing why you need to know, I would suggest that you make your own chart. Start at the top of the sight glass, draw off a gallon, record the measurement, rinse and repeat to the bottom of the sight glass. Note that this will include the volume out in any drips, if there is a wet return, so long as the water level is above the Hartford loop.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    EBEBRATT-Ed Member Posts: 15,312
    The spec sheet I found says 7.4 gallons. Search Dunkirk's website
  • Greg_44
    Greg_44 Member Posts: 5
    Where did you find this info? I could only find the low water cutoff water gallons capacity of 5.7 gals.