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Excessive water in sight-glass of Peerless Series 63/64 steam boiler

Hi! Happy Thanksgiving to all of you on this frigid day in NYC (21F outside now). All plumbing stores are closed so I desperately seek advice on this holiday to fix a problem before my 2010-old boiler busts.

I noticed my sight-glass is full and its not dirty (crystal clear water). To lower the sight-glass water level, I turned off the boiler and then drained the water from the boiler and red-rusty water came out until the boiler was mostly drained. But, that sight-glass level remained as is--the water level remained unchanged! When I turned on the boiler, the low-level water feeder's yellow light indicator (low-water level) turned on, and then its green light (water-feeder in operation) turned on as it started automatically to intake more water into the boiler, and then the water feeder turned off after 5 minutes (all of this suggests the low-level water feeder functions properly--not sure of this though). The pressuretrol gauge indicates 50 PSI and this has been consistent throughout (even when I pressed it to re-set the gauge and even when the boiler was drained) so I am not sure this is relevant to the puzzle. A prior post (from some research on this site) indicated that the "one cause of excess water can be excess pressure forcing water out of the boiler into the returns, and activating the water-feeder" (nicholas bonham-carter, 2012). Please advise so that I can lower my water level in the sight-glass to the normal level. FYI: my plumber was too busy this season to perform a basic maintenance on my boiler this year.



  • neilcneilc Member Posts: 805
    are both valves open to the sight glass?
    maybe the bottom is plugged to the boiler.
    need to know what that water level really is,
    or shut that boiler off.

    the gage reads 50? or 5?
    your gage shouldn't even go to 50, and reading 5 is still too high.
    Ptrol set low?
    pigtail clear?

    post a picture of the boiler and its controls and gage
  • castironcastiron Member Posts: 2
    Sounds like gauge glass valves are clogged which is common if you don’t keep up with servicing
    And the gauges on peerless boiler usually break being not installed on pigtail
    But if you drain boiler till LWCO light comes on and auto fill starts and light goes off your water level should be fine for now still you get boiler cleaned out on water side
  • Dan_NJDan_NJ Member Posts: 118
    When I blow down my sight glass there's always some crud in the lower valve. Over time it would probably clog completely if not for the valve I put on there to flush it out now and then. Check out Gordo's video here:
  • Dan_NJDan_NJ Member Posts: 118
    edited November 2018
    And when you're ready to add one of these to your sight glass here's a walkthru:
  • FredFred Member Posts: 8,418
    Shut the power off to the boiler, drain it again and that the sight glass and the valves on top and bottom off and clear the tappings that the valves are mounted into. They are clogged. Is the Gauge mounted off of a side tapping on the sight glass? If so, it is also affected by the clogged boiler tappings but I think you are mistaken. Those gauges don't typically go to 50 PSI. 30 is usually the top of the range. The gauge may also be broken.
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