My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was about
three times faster than the slow speed. The cycle is about six seconds
at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

On Sunday, October 22, 2017 at 10:51:04 PM UTC-4, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was about
three times faster than the slow speed. The cycle is about six seconds
at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

Have you checked all the toilets? A leaking flapper and the toilet topping off will create a cycle, but 6 secs is fast.

On 10/22/2017 10:50 PM, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner running fast and slow, not at a constant speed. The high speed was about three times faster than the slow speed. The cycle
is about six seconds at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

I'd look for a malfunctioning device with an automatic fill valve like a toilet, water softener, swamp cooler, commercial ice machine, hot water heating system or furnace humidifier.

On 23-Oct-17 12:39 PM, trader_4 wrote:
On Sunday, October 22, 2017 at 10:51:04 PM UTC-4, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was about
three times faster than the slow speed. The cycle is about six seconds
at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

Have you checked all the toilets? A leaking flapper and the toilet topping off will create a cycle, but 6 secs is fast.

If a leaky flapper is the problem, the spinner should stop spinning for
a short period, assuming the filling rate is faster than leaking rate.
When the water tank is full and before the tank is filling again, the
spinner should stop.

On 23-Oct-17 3:18 PM, Bubba wrote:
On 10/22/2017 10:50 PM, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was
about three times faster than the slow speed. The cycle is about six
seconds at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

I'd look for a malfunctioning device with an automatic fill valve like a
toilet, water softener, swamp cooler, commercial ice machine, hot water
heating system or furnace humidifier.

Among the devices you mentioned, I only have toilets.

This meter is for a multi-unit building. I have shut off valves to every
unit. Yet, it still leaks. That's why I believe it is the water line
that's leaking, not the devices connected to the water line.

On 10/22/17 9:50 PM, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was about
three times faster than the slow speed. The cycle is about six seconds
at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

I doubt it's the problem but will mention it anyhow.
Irrigation wells
will pump air at times and that can cause surging. Someone would likely
notice
that though.

On Monday, October 23, 2017 at 5:42:34 AM UTC-4, Lenny Jacobs wrote:
On 23-Oct-17 12:39 PM, trader_4 wrote:
On Sunday, October 22, 2017 at 10:51:04 PM UTC-4, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was about
three times faster than the slow speed. The cycle is about six seconds
at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

Have you checked all the toilets? A leaking flapper and the toilet topping off will create a cycle, but 6 secs is fast.

If a leaky flapper is the problem, the spinner should stop spinning for
a short period, assuming the filling rate is faster than leaking rate.
When the water tank is full and before the tank is filling again, the
spinner should stop.

You're assuming it's just one leak. There could be more than one, with
only one, eg toilet, cycling. You said the water line is leaking, where
is it leaking? You've found the leak, seen it or know for sure where it
is, eg underground? Isolate the rest of the system from that and see
what happens with the meter?

On Monday, October 23, 2017 at 5:46:49 AM UTC-4, Lenny Jacobs wrote:
On 23-Oct-17 3:18 PM, Bubba wrote:
On 10/22/2017 10:50 PM, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was
about three times faster than the slow speed. The cycle is about six
seconds at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

I'd look for a malfunctioning device with an automatic fill valve like a
toilet, water softener, swamp cooler, commercial ice machine, hot water
heating system or furnace humidifier.

Among the devices you mentioned, I only have toilets.

This meter is for a multi-unit building. I have shut off valves to every
unit. Yet, it still leaks. That's why I believe it is the water line
that's leaking, not the devices connected to the water line.

If you're sure that the line is totally shutoff where it enters the
building, then a leak, presumably underground is what's left. I
suppose that could be cycling, though it seems odd. I guess you'll
find out when you fix it.

On 23-Oct-17 4:46 AM, Lenny Jacobs wrote:
On 23-Oct-17 3:18 PM, Bubba wrote:
On 10/22/2017 10:50 PM, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was
about three times faster than the slow speed. The cycle is about six
seconds at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

I'd look for a malfunctioning device with an automatic fill valve like
a toilet, water softener, swamp cooler, commercial ice machine, hot
water heating system or furnace humidifier.

Among the devices you mentioned, I only have toilets.

This meter is for a multi-unit building. I have shut off valves to every
unit. Yet, it still leaks. That's why I believe it is the water line
that's leaking, not the devices connected to the water line.

With a variable rate like that it's got to be something cycling; it's
quite likely one or more of the cutoff valves to individual units has
enough bypass to cumulatively have some flow for the low level; when
whatever is the culprit cycles it's the higher rate.

There's no ice maker in anybody's fridge in the entire complex???
That'd be unlikely it seems. Plus whatever else tenants have installed;
aquarium, who knows???

It would be a most unusual leak in physical piping itself that would
have such a characteristic unless the meter itself is flaky...is it old
mechanical or newer?

In a multi-unit, may need to go to location(s) where the feeds to each
unit split and use some sound-detection to hear (and hopefully be able
to isolate) which unit(s) are where the flow is going...

--

On Monday, October 23, 2017 at 10:28:41 AM UTC-4, dpb wrote:
On 23-Oct-17 4:46 AM, Lenny Jacobs wrote:
On 23-Oct-17 3:18 PM, Bubba wrote:
On 10/22/2017 10:50 PM, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was
about three times faster than the slow speed. The cycle is about six
seconds at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

I'd look for a malfunctioning device with an automatic fill valve like
a toilet, water softener, swamp cooler, commercial ice machine, hot
water heating system or furnace humidifier.

Among the devices you mentioned, I only have toilets.

This meter is for a multi-unit building. I have shut off valves to every
unit. Yet, it still leaks. That's why I believe it is the water line
that's leaking, not the devices connected to the water line.

With a variable rate like that it's got to be something cycling; it's
quite likely one or more of the cutoff valves to individual units has
enough bypass to cumulatively have some flow for the low level; when
whatever is the culprit cycles it's the higher rate.

There's no ice maker in anybody's fridge in the entire complex???
That'd be unlikely it seems. Plus whatever else tenants have installed;
aquarium, who knows???

It would be a most unusual leak in physical piping itself that would
have such a characteristic unless the meter itself is flaky...is it old
mechanical or newer?

In a multi-unit, may need to go to location(s) where the feeds to each
unit split and use some sound-detection to hear (and hopefully be able
to isolate) which unit(s) are where the flow is going...

--

He should open a faucet on each apt line when the valves are off and
see if there is any flow. I agree, it seems odd that an underground
(presumably) leak would cause the cycling.

On 23-Oct-17 10:10 AM, trader_4 wrote:
....

He should open a faucet on each apt line when the valves are off and
see if there is any flow. I agree, it seems odd that an underground
(presumably) leak would cause the cycling.

Good point, I had intended to write that specifically to isolate any
apartment that is _not_ leaking (altho I had figured given the state of
mostly unused check valves likelihood was that all will show some bypass
flow).

I think the likelihood of the leak being underground in piping itself is
vanishingly small -- like it just ain't agonna' be. Unless, as noted,
it's the meter itself has gone nuts.

--

On 10/23/2017 5:42 AM, Lenny Jacobs wrote:
On 23-Oct-17 12:39 PM, trader_4 wrote:
On Sunday, October 22, 2017 at 10:51:04 PM UTC-4, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was about
three times faster than the slow speed. The cycle is about six seconds
at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

Have you checked all the toilets?Â* A leaking flapper and the toilet
topping off will create a cycle, but 6 secs is fast.

If a leaky flapper is the problem, the spinner should stop spinning for
a short period, assuming the filling rate is faster than leaking rate.
When the water tank is full and before the tank is filling again, the
spinner should stop.

Flapper is one item. Overflow is another and that could be the slow
operation if the fill valve never closes completely.

On 10/23/2017 5:46 AM, Lenny Jacobs wrote:
On 23-Oct-17 3:18 PM, Bubba wrote:
On 10/22/2017 10:50 PM, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was
about three times faster than the slow speed. The cycle is about six
seconds at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

I'd look for a malfunctioning device with an automatic fill valve like
a toilet, water softener, swamp cooler, commercial ice machine, hot
water heating system or furnace humidifier.

Among the devices you mentioned, I only have toilets.

This meter is for a multi-unit building. I have shut off valves to every
unit. Yet, it still leaks. That's why I believe it is the water line
that's leaking, not the devices connected to the water line.

You shut the vales, but did that stop the flow of water? Old valve not
often use can still allow a good flow.

On 23-Oct-17 7:46 PM, trader_4 wrote:
On Monday, October 23, 2017 at 5:42:34 AM UTC-4, Lenny Jacobs wrote:
On 23-Oct-17 12:39 PM, trader_4 wrote:
On Sunday, October 22, 2017 at 10:51:04 PM UTC-4, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was about
three times faster than the slow speed. The cycle is about six seconds
at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

Have you checked all the toilets? A leaking flapper and the toilet topping off will create a cycle, but 6 secs is fast.

If a leaky flapper is the problem, the spinner should stop spinning for
a short period, assuming the filling rate is faster than leaking rate.
When the water tank is full and before the tank is filling again, the
spinner should stop.

You're assuming it's just one leak. There could be more than one, with
only one, eg toilet, cycling. You said the water line is leaking, where
is it leaking? You've found the leak, seen it or know for sure where it
is, eg underground? Isolate the rest of the system from that and see
what happens with the meter?

Multiple leaks? good point. Didn't think of that one.

Since I have isolated all buildings and the meter still shows leaking,
at least the outside pipe leaks somewhere. Once that is fixed, I then
can check whether there are other leaks.

On 24-Oct-17 4:11 AM, Ed Pawlowski wrote:
On 10/23/2017 5:46 AM, Lenny Jacobs wrote:
On 23-Oct-17 3:18 PM, Bubba wrote:
On 10/22/2017 10:50 PM, Lenny Jacobs wrote:
My water line leaks. When checking the meter, I found the spinner
running fast and slow, not at a constant speed. The high speed was
about three times faster than the slow speed. The cycle is about six
seconds at slow speed and two or three seconds at high speed.

I wonder what causes the fluctuation, water pressure?

I'd look for a malfunctioning device with an automatic fill valve
like a toilet, water softener, swamp cooler, commercial ice machine,
hot water heating system or furnace humidifier.

Among the devices you mentioned, I only have toilets.

This meter is for a multi-unit building. I have shut off valves to
every unit. Yet, it still leaks. That's why I believe it is the water
line that's leaking, not the devices connected to the water line.

You shut the vales, but did that stop the flow of water?Â* Old valve not
often use can still allow a good flow.

I did check the faucets. I noticed that the water pressure dropped.
However, I did not wait until all the water drained. That would have
taken a while.

On 24-Oct-17 2:37 AM, Lenny Jacobs wrote:
....

I did check the faucets. I noticed that the water pressure dropped.
However, I did not wait until all the water drained. That would have
taken a while.


Until you do, you can't show that isn't where the water's going...what
type of isolation valves are installed?

--

On Tuesday, October 24, 2017 at 8:10:54 AM UTC-4, dpb wrote:
On 24-Oct-17 2:37 AM, Lenny Jacobs wrote:
...

I did check the faucets. I noticed that the water pressure dropped.
However, I did not wait until all the water drained. That would have
taken a while.


Until you do, you can't show that isn't where the water's going...what
type of isolation valves are installed?

--

+1

Not sure one has to wait for all the water to drain. If you open the
highest faucet on each apt, there should be nothing to drain.
It's when you open a first floor faucet or basement faucet
when you have stories above it where there can be a lot that drains
out.

On 24-Oct-17 9:16 AM, trader_4 wrote:
On Tuesday, October 24, 2017 at 8:10:54 AM UTC-4, dpb wrote:
On 24-Oct-17 2:37 AM, Lenny Jacobs wrote:
...

I did check the faucets. I noticed that the water pressure dropped.
However, I did not wait until all the water drained. That would have
taken a while.


Until you do, you can't show that isn't where the water's going...what
type of isolation valves are installed?

--

+1

Not sure one has to wait for all the water to drain. If you open the
highest faucet on each apt, there should be nothing to drain.
....


Good point; particularly with a multi-level/multi-unit facility.
Isolate; then if there's a drip at the uppermost level that doesn't stop
you know the isolation valve isn't holding perfectly.

Didn't say how many units but a small bypass flow over several could add
up to a measurable amount in toto at the meter; still the cycling
phenomenon has to be related to some mechanical system somewhere it
would seem.

I suppose there is that outside chance the OP raised of a external
pressure source that is cyclic and the difference in flow be pressure
related...that could be checked by inserting a pressure gauge in that
line but such rapid cycling would not seem to be likely for a supply
system characteristic I would think of unless there's some sort of other
large industrial facility or the like that has such a demand; the
overall system pressure would be more nearly constant.

--

On 24-Oct-17 6:40 PM, dpb wrote:
On 24-Oct-17 2:37 AM, Lenny Jacobs wrote:
...

I did check the faucets. I noticed that the water pressure dropped.
However, I did not wait until all the water drained. That would have
taken a while.


Until you do, you can't show that isn't where the water's going...what
type of isolation valves are installed?

--
Ball valves.

On 24-Oct-17 8:46 PM, trader_4 wrote:
On Tuesday, October 24, 2017 at 8:10:54 AM UTC-4, dpb wrote:
On 24-Oct-17 2:37 AM, Lenny Jacobs wrote:
...

I did check the faucets. I noticed that the water pressure dropped.
However, I did not wait until all the water drained. That would have
taken a while.


Until you do, you can't show that isn't where the water's going...what
type of isolation valves are installed?

--

+1

Not sure one has to wait for all the water to drain. If you open the
highest faucet on each apt, there should be nothing to drain.
It's when you open a first floor faucet or basement faucet
when you have stories above it where there can be a lot that drains
out.


Good point. Didn't think of opening the highest faucet. I opened one on
the first floor.

On 25-Oct-17 1:35 AM, dpb wrote:
On 24-Oct-17 9:16 AM, trader_4 wrote:
On Tuesday, October 24, 2017 at 8:10:54 AM UTC-4, dpb wrote:
On 24-Oct-17 2:37 AM, Lenny Jacobs wrote:
...

I did check the faucets. I noticed that the water pressure dropped.
However, I did not wait until all the water drained. That would have
taken a while.


Until you do, you can't show that isn't where the water's going...what
type of isolation valves are installed?

--

+1

Not sure one has to wait for all the water to drain.Â* If you open the
highest faucet on each apt, there should be nothing to drain.
...


Good point; particularly with a multi-level/multi-unit facility.
Isolate; then if there's a drip at the uppermost level that doesn't stop
you know the isolation valve isn't holding perfectly.

Didn't say how many units but a small bypass flow over several could add
up to a measurable amount in toto at the meter; still the cycling
phenomenon has to be related to some mechanical system somewhere it
would seem.

I suppose there is that outside chance the OP raised of a external
pressure source that is cyclic and the difference in flow be pressure
related...that could be checked by inserting a pressure gauge in that
line but such rapid cycling would not seem to be likely for a supply
system characteristic I would think of unless there's some sort of other
large industrial facility or the like that has such a demand; the
overall system pressure would be more nearly constant.

--

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.

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.

--

On Tuesday, October 24, 2017 at 10:21:52 PM UTC-4, Lenny Jacobs wrote:
On 25-Oct-17 1:35 AM, dpb wrote:
On 24-Oct-17 9:16 AM, trader_4 wrote:
On Tuesday, October 24, 2017 at 8:10:54 AM UTC-4, dpb wrote:
On 24-Oct-17 2:37 AM, Lenny Jacobs wrote:
...

I did check the faucets. I noticed that the water pressure dropped.
However, I did not wait until all the water drained. That would have
taken a while.


Until you do, you can't show that isn't where the water's going...what
type of isolation valves are installed?

--

+1

Not sure one has to wait for all the water to drain.Â* If you open the
highest faucet on each apt, there should be nothing to drain.
...


Good point; particularly with a multi-level/multi-unit facility.
Isolate; then if there's a drip at the uppermost level that doesn't stop
you know the isolation valve isn't holding perfectly.

Didn't say how many units but a small bypass flow over several could add
up to a measurable amount in toto at the meter; still the cycling
phenomenon has to be related to some mechanical system somewhere it
would seem.

I suppose there is that outside chance the OP raised of a external
pressure source that is cyclic and the difference in flow be pressure
related...that could be checked by inserting a pressure gauge in that
line but such rapid cycling would not seem to be likely for a supply
system characteristic I would think of unless there's some sort of other
large industrial facility or the like that has such a demand; the
overall system pressure would be more nearly constant.

--

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.

Agree, that would indicate that the water is somehow leaving the pipe
on the apt side of the shutoff valve. If the leak was in the supply
line entering the house, before the valve, when you turn it back on
after awhile there should not be the sound of water rushing in to fill
the pipes. It sounds like whatever is leaking or taking the water
not only takes whatever is leaking past the shutoff valve, but also
some of the water that's already in the pipes. Which would suggest to
me that whatever it is, it's more likely on the lower levels. If you
had something leaking at the highest faucets I don't see that partially
draining the pipes when the shutoff valve is off.

On 25-Oct-17 7:55 AM, trader_4 wrote:
....

Agree, that would indicate that the water is somehow leaving the pipe
on the apt side of the shutoff valve. If the leak was in the supply
line entering the house, before the valve, when you turn it back on
after awhile there should not be the sound of water rushing in to fill
the pipes. It sounds like whatever is leaking or taking the water
not only takes whatever is leaking past the shutoff valve, but also
some of the water that's already in the pipes. Which would suggest to
me that whatever it is, it's more likely on the lower levels. If you
had something leaking at the highest faucets I don't see that partially
draining the pipes when the shutoff valve is off.

Siphon effects?

I'm curious what we're talking about in absolute flow rate when isolated
both the low/high rates. That could possibly lead to some klews as to
what would be that volumetric capacity.

And, has the "true isolation" test been run; granted if they're all ball
valves they have far better chance of actually holding than the more
typical gate valve...

What's the size(s) of the various lines out of curiosity?

--

On Wednesday, October 25, 2017 at 11:00:44 AM UTC-4, dpb wrote:
On 25-Oct-17 7:55 AM, trader_4 wrote:
...

Agree, that would indicate that the water is somehow leaving the pipe
on the apt side of the shutoff valve. If the leak was in the supply
line entering the house, before the valve, when you turn it back on
after awhile there should not be the sound of water rushing in to fill
the pipes. It sounds like whatever is leaking or taking the water
not only takes whatever is leaking past the shutoff valve, but also
some of the water that's already in the pipes. Which would suggest to
me that whatever it is, it's more likely on the lower levels. If you
had something leaking at the highest faucets I don't see that partially
draining the pipes when the shutoff valve is off.

Siphon effects?

I'm curious what we're talking about in absolute flow rate when isolated
both the low/high rates. That could possibly lead to some klews as to
what would be that volumetric capacity.

And, has the "true isolation" test been run; granted if they're all ball
valves they have far better chance of actually holding than the more
typical gate valve...

What's the size(s) of the various lines out of curiosity?

--

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.

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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On 25-Oct-17 1:35 PM, dpb wrote:
....

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.
....

That almost would seem to have to be the standing head of the upper
floors or a still-sizable pressure head from a leaking valve (or a
still-undiscovered other source path, mayhaps? There's actually a loop
in the feed to the house here from the well owing to how lines were
conjoined at one time lo! those many years when the second house was
moved out when folks moved to "the big house" after grandparents passed
and they refinished it and then sold "our" house and it was moved (back)
to town).

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