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Glass Gauge water question

pnm2 Member Posts: 56
According to Dan Holohan's "We Got Steam Heat!: A Homeowner's Guide to Peaceful Coexistence":

"It’s normal for the water [in the glass gauge] to bounce about three-quarters of an inch or so when the boiler is making steam.  If the bouncing is crazier than that the boiler probably needs attention.  A lot of things can cause bouncing and none of them are good.  Have a pro look at it."

Depending on what he means by "bounce", I may or may not have a problem. The water's, let's say, "micro-jolts" were probably within the 3/4-in. range he mentioned, but the level of the water would rise and fall a much greater length of the gauge -- maybe even nearly the full range of it.

So, is the level supposed to remain relatively static and should I therefore be concerned, or it's okay so long as those "micro-jolts" are rather small?


  • Jamie Hall
    Jamie Hall Member Posts: 23,303
    The small oscillations are quite normal -- as is a gradual drop in water level (perhaps a quarter of the glass) as the boiler comes up to full steam and the system fills -- though that will depend on the actual volume of the boiler relative to the system.

    A rise and fall of nearly the full length of the glass is not normal (and should, by the way, trigger a low water cutoff, if the cutoff is where it usually is). There are a number of different things which could be the problem...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • pnm2
    pnm2 Member Posts: 56
    Hmm...okay, with that in mind I'll take a closer look tomorrow and see just how much the level rises and falls. Thanks again!