On 25-Oct-17 1:01 PM, trader_4 wrote:
....[old conversation elided for brevity]...

Agree

I'd start by figuring out which valves work and completely shut off
and which don't to further isolate it. I'd also consider replacing
the valves that don't shut off completely, depending on how hard or
easy that might be. It has other benefits, sooner or later it's going
to be a problem with some other repair.
If the water is going into the building, then
it's very likely going down a drain. You'd think water would be
noticed somewhere if it's leaking. Has he tried listening to the
drain pipes with the water off? If it's real slow, probably wouldn't
work. But if it's a drip into the right kind of pipe, might
be able to hear it and further identify where it's coming from.
I'd also look for likely places where a pipe could go outside, feed
something else, or sillcocks, etc.

I'm in agreement w/ all the above, too, altho the curiosity of emptying
isolated line indicates the outflow exceeds the inflow past the
isolation valve(s) or there would be no empty volume to fill...that
makes the question of just how much water are we talking in absolute
flow rates of interest to figure out what could be that big (or small,
depending on what that number might be).

Then, there's still this thing that he says it cycles and at a pretty
rapid clip indicates to me the flow path, wherever it is, must actually
be pretty sizable and that it's driving force hasn't gone away with the
isolation...I'd like to figure out where that is coming from.

I'm also in agreement and pointed out it's beginning to sound more and
more like there's an unknown side tap on that line between the isolation
valve(s) he knows of and the supply -- I'd also already thrown out a
spate of ideas on what that might just be including the outside end uses
(in use or perhaps previously abandoned).

I've got an unused set of feedlots/pens here on the farmstead that are
on a spur...that valve(*) is closed off, but is, unfortunately, not a
ball valve and leaks pretty badly so the system is pressurized. There's
been a failure out there a time or two in the old supply lines to the
tanks that have had to patch...at least I do know where those are as we
put them all in; if were a purchased property like a rental no telling
what formerly might have been...

(*) And, yes, this one is deep-enough and in such a location it's just
not as of yet been worth the hassle to replace even though it really,
really, should be because it's a branch of the main that feeds the house
and there's no isolation to it that doesn't also cut the house off when
something does happen...

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