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    Air purger leak (5 Posts)

  • Weezbo Weezbo @ 1:16 PM
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    well, you could install a Caleffi air eliminator with a check

    valve.... that or completely eliminate the air scoop and go with a slightly fancier gizmo used to collect and eliminate entrained air...before you have to replace the captive air tank due to work done on it by outside agency (oxidation) often the configuration you have will Burn pinner holes in the tank as it rusts away through time....
  • hot rod hot rod @ 5:45 PM
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    Also from Caleffi

    is a one way check cap to prevent air from being sucked in with a high head "mis-placed" circ. And Caleffi uses a hydroscopic disc, on some models. The disc responds within 2 seconds to stop fluid discharge. it releases air again when it dries. Quite clever! The chrome one is a hydroscopic vent with a check valve to ease replacement. And the check shut off valve mentioned above. hot rod
  • Vic Vic @ 10:25 AM
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    Air purger leak

    OK, maybe the big brains out there can help me with this one. I have this American BS3 air purger in the hot water heating system in my home. There's a gizmo screwed into the top of it (see pic)that sometimes leaks water. The water runs down the unit drips on the expansion tank and then onto the boiler. I hung a quart container under the tank to keep the water from dripping on the boiler. For a couple of months there was only a little water in the cup. The amount didn't increase nor did it evaporate (hmmmmmm...?). Then one day I noticed that the container was nearly full. I emptied it. That was about two weeks ago. No leak since. What the heck's going on? Thanks
  • Brad White Brad White @ 10:42 AM
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    Gizmo

    You need to get your terminology straight, Vic. That "gizmo" is called a "thingee", got it? :) It is an automatic air vent that took on being an automatic water vent as a hobby. There is a float inside which when supported by water under pressure seals the vent hole. There may be debris preventing it from closing fully, or a failed float. It is a quick fix to replace it, but unless you drain your system or isolate this section, it can be a wet one. Now, that you have this leak, it may also be a function of excessive water pressure in the system. The relief valve should (should) take care of that, but on the off-chance, what system pressure are you running? Low likelihood but I thought I would ask. Also, is the circulator downstream of this vent, purger and expansion tank setup? If it is upstream, you could well be drawing air into that vent at times. This in turn causes all kinds of problems, another topic. But one thought in this regard is that if the circulator runs intermittently, it could well be drawing in air and when the circulator stops, it "exhales" slightly. If the vent is blocked open by a flake of rust (Rust? Really? From where? He asked rhetorically...) you have an open system occasionally.. My $0.02 Brad
  • Vic Vic @ 3:36 PM
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    Air purger leak

    > You need to get your terminology straight, Vic.
    > That "gizmo" is called a "thingee", got it?
    > :)
    >
    > It is an automatic air vent that took on
    > being an automatic water vent as a hobby. There
    > is a float inside which when supported by water
    > under pressure seals the vent hole. There may be
    > debris preventing it from closing fully, or a
    > failed float. It is a quick fix to replace it,
    > but unless you drain your system or isolate this
    > section, it can be a wet one.
    >
    > Now, that you
    > have this leak, it may also be a function of
    > excessive water pressure in the system. The
    > relief valve should (should) take care of that,
    > but on the off-chance, what system pressure are
    > you running? Low likelihood but I thought I would
    > ask.
    >
    > Also, is the circulator downstream of
    > this vent, purger and expansion tank setup? If it
    > is upstream, you could well be drawing air into
    > that vent at times. This in turn causes all kinds
    > of problems, another topic. But one thought in
    > this regard is that if the circulator runs
    > intermittently, it could well be drawing in air
    > and when the circulator stops, it "exhales"
    > slightly. If the vent is blocked open by a flake
    > of rust (Rust? Really? From where? He asked
    > rhetorically...) you have an open system
    > occasionally..
    >
    > My $0.02
    >
    > Brad

    Oh, no rust here (hahaha). Pressure is about 28lbs on the boiler mounted gauge. Circulator is at the return end of the loop and feeds into the boiler. The purger and "thingee" are after the boiler and feed 2 zone valves, etc. Both loops rejoin to feed the circulator on return. The flake sounds like a good diagnoses. There is a small knob on top of the "thingee". I exercised this by turning one way then the other, returning it to the original position in case it was a control of some sort (is it?). That was at the time I attached the leak catcher container (high tech lingo). After that is seemed fine for a couple months. Then a quart of water leaks into the container. Then nothing for the past 2 weeks. I'm hoping not the have to replace this whole mess for awhile, but it is approaching the 30 year mark. The service guy tells me its running about 86% efficient, and I don't think I can get something much better, of course I could be wrong. Its been known to happen, just ask my wife. ;)
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