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    Backflow preventer question (11 Posts)

  • Steve Nichols Steve Nichols @ 1:04 PM
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    Backflow preventer question

    Hey all,
    I'm helping a neighbor skim his steam boiler (very dirty) and I am running into an issue that has confused me a bit.  The installer put a backflow preventer in between manual feed valve and boiler.  The valve has a copper pipe that comes out the side (vent?) and down into a big 5 gallon bucket.  Everytime homeowner fills boiler via valve, a ton of water shoots out backflow valve and some into the boiler.  This makes doing a slow skim challenging.  Having never worked with a BFP, I dont know what's normal, but this just doesn't appear correct.
    Can they be installed "reversed" and cause this to happen?  Could there be crud in the valve?  I started to feed the water and covered the end of the copper "downpipe" with my thumb.  When I removed it, the flow had minimized and we are now able to keep a flow going into the boiler to do the skim. 
    Thanks in advance,
    striving for peaceful coexistence with an oversized boiler....
  • MTC MTC @ 1:39 PM
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    If you can post pictures...

    they're often worth 1000 or more words, when trying to troubleshoot these things.
  • Steve Nichols Steve Nichols @ 2:01 PM
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    pictures a comin

    MTC, I'm heading over there shortly,  I'll grab my camera.
    striving for peaceful coexistence with an oversized boiler....
  • Paul48 Paul48 @ 2:42 PM
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    it's backwards you won't get anything through it. It should have a direction indicator on it.
  • Steve Nichols Steve Nichols @ 3:24 PM
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    heres the pic

    Thanks Paul,
    I think it's quieted down.  Might have been some crud or something.  Attached find a picture of the current setup.  I couldn't find a direction indicator on it.
    striving for peaceful coexistence with an oversized boiler....
  • icesailor icesailor @ 7:24 PM
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    It will say "Inlet" and "Outlet" on it.
    It is required to be there. If it leaks through the outlet, it is doing what it is supposed to do.
  • Paul48 Paul48 @ 7:49 PM
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    The arrow in the picture, might be a clue!
  • Steve Nichols Steve Nichols @ 10:01 PM
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    boy do I feel stupid

    You gotta be kidding. I had my face right up against that thing and I couldn't see that, and I just got new glasses.  Must be time for reading glasses.   Sorry for wasting your time guys, I should have seen that, but didn't.    The thing was acting screwy, though and shooting all the feed water down the vent and virtually nothing into boiler.  But after I plugged the end with my thumb, it stopped and went into boiler with a minimal trickle down vent.
    striving for peaceful coexistence with an oversized boiler....
  • Paul48 Paul48 @ 10:22 PM
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    replace it, on general priciple. It shouldn't function like that.
  • Steve Nichols Steve Nichols @ 11:06 PM
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    will do

    Thx Paul, I'll suggest the HO replace during summer.  Hopefully today's skim makes it behave a lot better.   To me it appears that the steam pros that sized it did really well matching connected radiation to boiler size.  It doesn't really trip off on pressure all that much despite main venting that could be better. 
    striving for peaceful coexistence with an oversized boiler....
  • SWEI SWEI @ 11:07 PM
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    will do exactly that.  Once it's gone you should be fine unless it damaged the seat or the gasket (in which case you'd see a drip or a dribble.)  It's also possible the pivot/shaft/spring/something in the mechanism is borked, but working the valve open and shut a few times should suss that out.
    This post was edited by an admin on February 16, 2013 11:09 PM.
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