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losing water

dc07736dc07736 Member Posts: 15
100 y/o system 12 cast iron radiators, used steam boiler, burnham 142,000 btu, all new accessories including lwco. steam heat works beautifully. losing 2 gal of water in 4 hours each day we turn it on for a test. we checked the boiler and it doesn't seem to be losing any water. 90% of the pipes are visible in the basement. we can't find any leaks. we never hear any banging noises. Where is the water going? kingston ny...


  • JUGHNEJUGHNE Member Posts: 6,626
    Do you have any return pipes under the floor or some that you can not see. Buried wet returns can leak into the ground and never show up as water on the floor...or
    Do you see steam coming out of the chimney when it is firing?

    You can do a simple test to see if the boiler has leaks above the water line. With the boiler nearly cold and off just overfill it to where you just feel the steam pipe leaving the boiler get cold from the water you are adding. Let it sit for 30 minutes and look for water leaking onto the floor. This will usually show a hole in the cast iron if you have one.
  • FredFred Member Posts: 8,374
    Most likely going up the chimney as steam. A hole in boiler above the water line. Do as @JUGHNE suggests and I suspect you will see water run out from under the boiler. You can also check the chimney when the boiler is steaming and see if there is a cloud of steam coming out of the top of it.
  • JUGHNEJUGHNE Member Posts: 6,626
    Looking back for this OP there were some water return issues.
    So are there buried returns?
  • kcoppkcopp Member Posts: 3,433
    How about the vents? Are the rad vents closing or is there a main vent or two not sealing? That will lose you a bunch of water.
  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,109
    Start by overfilling the boiler, when cold, up to the header, and let it sit for a couple of hours. If the boiler is leaking, it will be apparent in the firebox, or on the floor.
    If no leaks are to be seen, then drain the water down to a visible marked point on the sight glass, and wait for an additional couple of hours. Any fall in level would indicate a leak in the wet returns.
    If the system passes these tests, then start looking for any non-closing main vents.--NBC
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