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Leaking boiler?

Boiler hasn't been used for more then a week, shut off at the boiler. the water in the sight glass is slowly finding its way out of the sight glass. i don't see anything around the boiler. The rads are dry. the vents are no longer leaking or hissing like they were before. i've lost about 3 tablespoons of water since it was last used october 5th. Could this be general evaporation of water or could there a leak somewhere deeper?


  • mattmia2
    mattmia2 Member Posts: 7,148
    How do you know you only lost 3 tablespoons?

    Do you have any returns under the floor?
  • Fmassarotto_9
    Fmassarotto_9 Member Posts: 94
    mattmia2 said:
    How do you know you only lost 3 tablespoons? Do you have any returns under the floor?

    i say 3 tablespoons because that's what seems to be missing from the sight glass since i last checked less then a week ago. that's the only way i can personally identify the water level. then if there is more or less it's beyond my knowledge 

  • pedmec
    pedmec Member Posts: 712
    Mark the glass with a marker then tell us in inches
  • neilc
    neilc Member Posts: 2,084
    your 3 tablespoons in the sightglass is gallons+gallons in the boiler
    known to beat dead horses
    JUGHNE Member Posts: 10,278
    Need pictures of that side of the boiler showing all the piping, floor to ceiling.
    Include Hartford Loop and return connections.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 4,913
    edited October 2022
    Is it possible to loose water in the sight glass only and the boiler stay the same? Then the 3 tablespoons would be most accurate. That is if the measurer of the leaking tablespoon actually knew that 3 tablespoon inside of a 3/8" inside diameter (ID) glass tube would change the water level about 9".

    But accuracy is not that important when asking questions of this importance.

    This is surely a case of: "you know what I mean"

    But if you don't isolate the water in the boiler from the water in the glass tube, then the 3 tablespoons become a whole different story. Suppose the boiler is very small and only holds 10 gallons of water. Since there are approximately 767.9999 tablespoons of water to the gallon, then 3 tablespoons of water missing from this small boiler would amount to a whopping 0.0000039% of that water. Hardly an insignificant amount of water to just set aside as possible evaporation.

    Much more research is needed to determine if the 3 tablespoons are from the sight glass only resulting in a 9" drop. Or if the entire boiler lost 3 tablespoons. And was the tablespoon that was used to measure the water loss SILVER? ...and... Who's mouth was it removed from?

    Just some non-serious questions to be answered in order to get to the bottom of this mystery.

    I'm sure this information has no bearing on the problem at hand, and is in no way helpful.

    Edward Young Retired HVAC Contractor & HYDRONICIAN Services first oil burner at age 16 P/T trainer for EH-CC.org
  • reggi
    reggi Member Posts: 313
    I'll ask.... how do you know your radiators are dry ? Just curious 
    One way to get familiar something you know nothing about is to ask a really smart person a really stupid question
  • Fmassarotto_9
    Fmassarotto_9 Member Posts: 94
    reggi said:
    I'll ask.... how do you know your radiators are dry ? Just curious 
    well the boiler hasn't been on, no steam is being used. it's just slowly leaving the sight glass. 
  • neilc
    neilc Member Posts: 2,084
    edited October 2022
    known to beat dead horses
  • SeanBeans
    SeanBeans Member Posts: 505
    Are the sight glass valves open? Are they stuck closed?