Leak test a water hydrant/facuet ?

[JRobyn]

The problem would be that the hydrant valve is slightly leaking and the weep/drainage is OK, allowing the leaked water to drain off without filling the riser pipe (except for maybe just a little).

I think shutting off the upstream supply and then monitoring the pressure in the line is your best test method. At least as long as you are pretty sure that the shutoff valve doesn't leak just slightly. Unfortunately in my experience, most valves, with the possible exception of teflon-seat ball valves DO leak just slightly. If the pressure stays solid within 5-10psi over a time period of an hour or two, that would indicate to me that everything is as tight as could be expected.

- Jay

 

[CobyRupert]

If the hydrant is leaking with it shut off especially with pour drainage won't water be dripping from the top when it's off. That's how I discovered one of mine was leaking and had to adjust the rod.

Yes, in the summer it would drip from the top if the leak rate is greater than the soil absorption rate out the weep hole (and given a long enough time for the difference to fill the 7' tall pipe and come out the top. That could take a while.). In the winter, however, the water would slowly fill the stanchion pipe until it freezes solid (no drip).
-OR the seal could be fine, but the soil is saturated and the stand pipe doesn't drain when you shut the valve off and the water left in the pipe freezes. Hard to diagnose from above ground.

The problem I'm trying to eliminate is "Does the seal leak?".

The problem would be that the hydrant valve is slightly leaking and the weep/drainage is OK, allowing the leaked water to drain off without filling the riser pipe (except for maybe just a little).

I think shutting off the upstream supply and then monitoring the pressure in the line is your best test method. At least as long as you are pretty sure that the shutoff valve doesn't leak just slightly. Unfortunately in my experience, most valves, with the possible exception of teflon-seat ball valves DO leak just slightly. If the pressure stays solid within 5-10psi over a time period of an hour or two, that would indicate to me that everything is as tight as could be expected.

- Jay

Thanks, that's the kind of info I was looking for.

I realize I might have any (or all of) the following problems:
1- Leaky valve seal
2- Bad/saturated weep hole drainage (which could be caused by #1)
3- Too shallow of a feed line (upstream of the valve) / Really, really deep frost this year.

-I'm trying to diagnose/eliminate #1 at this point (well, when it thaws)
I'm going to install a pressure gauge at the supply end in my house basement to check the valve. I'm also going to install a cleanout (tee) at the supply end so that I can run 1/4 tubing through the line with a hot water supply hooked to it, the idea is to feed the hot water tubing down the 1-1/2" water line with a stiff wire-snake.

 

[ovrszd]

Water is stable. Just like Hydraulic Fluid. It cannot be compressed measurably under normal conditions. So. Install your gauge, pressurize the line, seal it off. If you have the slightest leak you will, within a very short time, see your pressure drop to zero. Only expansion that can be overcome is the stretch in the plumbing. That is why I said "within a very short time". A slow leak will allow the plumbing to decompress before the pressure drops considerably.

I think you already realize you have a leak in your hydrant shutoff mechanism. As others mentioned you can probably adjust it and stop that. If not, as others mentioned, you can pull the mechanism out of the hydrant without digging it up and replace the rubber seal at the bottom of the hydrant rod. And as others mentioned, your seep hole issue is secondary and digging is required to fix that problem, even if it's something so simple as the weep hole crusting shut over time.

 

[CobyRupert]

Thanks ovrszd. I was looking for confirmation.
I think the pressure switch will be a good tool to prevent problems going into next winter, and to save my well pump from cycling on/off over the summer if a seal goes bad.
Winter is NOT the time to find this out.
The problem is my wife/and daughter operate the valve 99.9% of the time, so things that "should' be detectable : I.e. the plunger rod has slipped on the handle, or you don't hear the water immediately draining (detect a vacuum) upon shut-off, or the effort to operate the handle changes, etc.. it won't get detected until it something goes really wrong.