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Waterline Issues - Dirty and Dropping

BobbyC Member Posts: 96
Hi Guys,

i posted threads earlier about my new install.  Things seem to be running well although it hasn't been that cold.  Received Dan's book on Saturday and started reading it.  I never realized how much of a sense of humor Dan has.  Some of the stuff is downright hillarious.... 

Two things I still notice about my system is that the water is still a little dirty (rusty looking) and that when the system is on and after the mains fill up with steam and the rads mains start to fill up the water line plunges to about .5-1 inch above the bottom of the sight glass.  When it's not running the water line returns to it's orginal point of about 1 inch from the top of the sight glass.  I dont see too much "surging" going on but it's a pretty sudden drop at a pretty specific time. 

Rod, I know you mentioned that this seems normal and that the returns are clean if the water comes back to the original point quickly but thought I would throw it out there again.......


  • Jamie Hall
    Jamie Hall Member Posts: 19,968

    the water went down low enoug to trip an automatic feeder, or stayed down for more than a very short time after the burner shuts off, I'd agree with Rod -- sounds more or less normal.  What you may be seeing is the difference between the behaviour of an older boiler, with lots of water in it, and a new boiler with very little water in it by design.  It takes the same amount of water to 'stack up' in the returns in both cases -- but that makes a bigger change in level in your new little pot than it did in the old bigger pot.

    On the other hand, if it takes some time for the water to come back, it could be cruddy returns -- which may or may not cure themselves, given time.  Still, if the water doesn't bounce, and stays within the gauge glass while firing... I'd just observe it over time, and not worry about it.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • BobbyC
    BobbyC Member Posts: 96
    Thanks Jamie

    That makes sense.. It's not cycling off with the LWCO or tripping my feeder and I tell ya it rises back up to the top of the sight glass pretty damn quick after the boiler shuts down so I'll just monitor it for now.
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