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End of Line trap blockage

elfie Member Posts: 264
in this situation, the end of main F&T trap is clearly blocked (ie. condensate pipe on the other side is stone cold)

the main feeds a few radiators that have condensate return lines feeding another condensate return pipe

eventually, i suspect the steam main would accumulate and fill up with condensate (there is pipe banging)

the main is still very hot where it meets the trap.

how long will it be before the main fills up with water? and what other problems can happen?


  • Jamie Hall
    Jamie Hall Member Posts: 17,080
    It depends...

    a lot on the pitch of that steam main.  If it pitches back to towards the boiler, or to a drip to a return, it may never fill up -- but it is very likely to bang.  On the other hand, if that is the low end, it's already filled up as much as it's going to be...  biggest problem, unless the main fills to the point where it cuts off flow to one or more radiators, is water hammer.

    F&T's aren't that hard to repair, and most of them can be.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
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