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Still losing water

dc07736dc07736 Posts: 15Member
Still losing 2 gallons of water on each test.
Each day we bring water up to correct level.
Turn boiler on early , let run for 4 hours, then turn it off.
24 hours later we are missing 2 gallons of water.

Good heat very fast, 12 cast iron radiators , 100 years old.
We installed a used Burnham steam boiler 142,000 btu, natural gas.
All new 24 volt assesories.
No banging noise.

Checked everywhere for leaks.
Did as you suggested, overfilled boiler when cold,
Let set 24 hours, no leaks in boiler . No water anywhere on cast iron when overfilled and cold.

When boiler is hot we check exhaust for steam, none in exhaust , none coming out chimney.
Checked all returns for leaks.

All air vents are new , 2 main steam vents are new.
Can find no steam or water leaks.

System works great other than losing water.
Is this a lot of water to lose in such a short time?
Historic house in Kingston NY


  • lchmblchmb Posts: 2,927Member
    yes it's to much. You need to locate where it is going... not only will the fresh water destroy the boiler, if your putting that much moisture into the house you'll cause other issues..
  • nicholas bonham-carternicholas bonham-carter Posts: 7,829Member
    When you overfilled the boiler, did you make sure the water level was above the header, well above the height of the boiler sections?
    Just filling above the top of the sight glass will not test for a hole in the sections top.
    2 gallons lost in 4 hours is more than any leaking vent could be responsible for, although underground wet returns could lose that much.--NBC
  • Jamie HallJamie Hall Posts: 10,465Member
    You overfilled the boiler and the level didn't drop? But it drops while it's running? Steam leak somewhere, eh? Or -- if when you overfilled the boiler and it didn't drop, did you have a valve to the wet returns closed? If so, and it drops with that valve open... wet return leak is quite possible.

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • nicholas bonham-carternicholas bonham-carter Posts: 7,829Member
    edited April 2017
    While the boiler is still off, do the following: Mark the normal sight glass level after doing the overfilling, and it will show any level drop due to a leak in any buried wet returns.
    This leak may well have killed the previous boiler with too much constant fresh oxygenated water being added.--NBC
  • JUGHNEJUGHNE Posts: 5,673Member
    edited April 2017
    Do I understand correctly that if there is a Hartford Loop with leaking wet returns the boiler water line should not drop.....the very intent of the HL I believe?.....With the boiler off and cool.

    Are all wet return pipes visible above the floor?

    When did the water loss start?

    There was a posting years ago of a new homeowner losing water and eventually found a hole purposely drilled in the bottom of a sagging steam main, done to get rid of some water hammer.....was in a dirt crawl space and hard to see.
  • FredFred Posts: 7,863Member
    If my memory serves me right, I thought you said you had a short section of wet return under the basement floor. If so, that's the place to look. It's draining into the ground.
  • JUGHNEJUGHNE Posts: 5,673Member
    In the previous thread you stated that 90% of the piping is visible.
    Where is the other 10% located? Under the floor or behind a wall?
    The buried wet return pipes question still stands.
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