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Condensate on boiler sight glass

triggerhappy24 Member Posts: 42
edited December 2018 in Gas Heating
As some of you guys and gals have seen I work with some big water tube boilers that make high temp hot water (at 370 degrees) one of the boilers from time to time leak on the out side front of the boiler under the fresh air box. I have suggested along with a few others that there may be a leaking tube in side of the boiler. But one of the guys insist that if a tube was leaking inside the box there would be some Condensate on the sight glass of the boiler. With my inexperienced I was wondering on how true that is? I mean that box gets hot!! Wouldnt the condensation evaporate really quickly inside that box? Well before there was enough to create the condensation? Has anyone any insight to that theory?

P.s. sorry if this is under the wrong category, want really sure on where to stick this question


    EBEBRATT-Ed Member Posts: 10,276
    Condensate around the fresh air box has me thinking about warm moist air hitting the cold make up air and condensing. A leak in a high temp HW boiler I don't think you would see any water. It would instantly flash to superheated steam which is invisible.

    I don't claim to be a HTHW boiler expert by any means
  • Jamie Hall
    Jamie Hall Member Posts: 17,061
    I'm no expert either -- but on steam boilers, anyway, any leakage into the fire side is zapped into steam and goes out the stack... probably wouldn't see it there, either, unless it was really bad.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • triggerhappy24
    triggerhappy24 Member Posts: 42
    Thanks guys for the comments. This is what I presumed also, I was just wondering for my self what was right. My chief is not always right but it's hard to tell when he's right and when he's give BS. I was also wondering about the combustion not being hot enough to possibly cause some type condensate in the stack. The funny thing is the leake seams to be on the body of the boiler and not on the fresh air box itself. And the fresh air box is about a foot away from the front of the boiler. I know the 2 parts meet eventually though. We did collect a water sample, it did not test positive for the chemical that is in are HTW so it is condensate from somewhere and some how. There is just no 100% evidence on where it is coming from.