On 24-Oct-17 9:21 PM, Lenny Jacobs wrote:
....

Didn't think of bypass flow. However, if there is no leak, the bypass
flow won't go anywhere and the meter should not run. I'm sure faucets
and toilets don't leak.

Another thing I noticed after the first post is that if I shut off the
main valve for few hours then turned it back on, I could hear water
gushing through the pipe. That indicates the pipe was empty, right?
Can I assume that the pipe from the main valve to the lowest toilet
valve (faucet valve is always higher than toilet valve if on the same
floor) is at least partially empty? If that assumption is good, that
would indicate at least one leak is between the main valve and the
lowest faucet valve.

Noticed in other report there are, you say, ball valves--that's pretty
unusual but higher probability then that they are really sealing than
the typical contractor-install. Would still do the above test to be
certain, but looks less likely than previously figured, indeed...

There's still the outside service...and it sounds like perhaps there's a
split of the feed before the inside(?) isolation valve. What about a
pool/spa (perhaps now abandoned), irrigation system, etc., ...?

It's the cyclic nature you're seeing that seems most unlikely is "just"
a simple piping leak.

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