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ktgatlin
06-03-2008, 03:58 AM
This might be a beginner question. I was just wondering if there is such a thing as a leak down test, either Hyrdo or Air for PVC lines.

In essence it would mean capping all the main and branch lines and then pressurizing the lines with air or water with PSI guage on the line.

Leave the "fluid" in the lines for a set amount of time and look for slippage on the PSI guage.

I did research and found that pressurizing PVC lines with air can be a bad thing. It sounds like PVC can shatter like a grenade, especially pressurized with air.

I did a few checks like this before burying my lines and I found a few leaks, 2 leaks.

I laid out a majority of my lines in PVC. I will be running some 1/2 and 1/4 in poly but those runs will be pretty short.

Thanks

ktgatlin

DanaMac
06-03-2008, 08:45 AM
This might be a beginner question. I was just wondering if there is such a thing as a leak down test, either Hyrdo or Air for PVC lines.

In essence it would mean capping all the main and branch lines and then pressurizing the lines with air or water with PSI guage on the line.

Years ago when I worked for someone else, we installed two systems for state run rest stops along the highway. We had to do a pressure test like you mentioned on the mainline. Used air, no liquid. But I don't remember specifics on it.

Wet_Boots
06-03-2008, 08:55 AM
You don't need high pressures for leak testing, so the usual PVC caution needn't apply. In the real world of lawn sprinkler zones, a dripping fitting on a zone is no biggie.

WalkGood
06-03-2008, 09:00 AM
I laid out a majority of my lines in PVC. I will be running some 1/2 and 1/4 in poly but those runs will be pretty short.


I've never seen 1/4 poly. :confused:

DanaMac
06-03-2008, 09:05 AM
I've never seen 1/4 poly. :confused:

1/4" spaghetti drip tubing maybe...

Kiril
06-03-2008, 09:20 AM
Take a pressure test at the distal end of each of your zones on install, then you have a baseline pressure to work with in order to diagnose zone performance and any possible leaks.

FIMCO-MEISTER
06-03-2008, 09:33 AM
You don't need high pressures for leak testing, so the usual PVC caution needn't apply. In the real world of lawn sprinkler zones, a dripping fitting on a zone is no biggie.

Ditto... Not sure why you'd get a hangover about small leaks in lateral line pipes. One technique we use on mains is to shut the water down at the dcva or poc. leave it off for 10 minutes. Turn it back on and if the meter needle jumps we have a small leak. No movement at all we are safe. Not a 100% perfect method but a low cost way to evaluate for leaks sometimes.

Waterit
06-04-2008, 01:47 AM
We do a lot of installs "on board" our local Navy base. They require pressure testing of all piping before it can be covered. We install everything except the funny pipe and screw teflon'd plugs into the end fittings. Then use a compressor to pump it up to about 75 PSI. If it holds with no more than a 2PSI drop over 2 hours, we are good to go.

Ridiculous? Of course. But that's the military for you.

ktgatlin
06-04-2008, 02:38 AM
We do a lot of installs "on board" our local Navy base. They require pressure testing of all piping before it can be covered. We install everything except the funny pipe and screw teflon'd plugs into the end fittings. Then use a compressor to pump it up to about 75 PSI. If it holds with no more than a 2PSI drop over 2 hours, we are good to go.

Ridiculous? Of course. But that's the military for you.

I did almost the same test on my system. Turned out pretty good. I also did a water test, plugged all the outlets (all 1/2 threaded) and found leaks.

My biggest issues were leaks on 1in threaded PVC fittings. I used both teflon paste and teflon wrap. Two of those MAs refused to comply and kept leaking. I redid it twice and still it leaked. I cut it out and did all glue socket fittings. I found these during wet testing.

Im not too worried about leaks in lateral lines. I used PVC for lots of my supply lines. I should have planned on using more PE instead of PVC. I just went with what I knew and was comfortable with. I will still use PE but I ran PVC lateral lines to major pick up points where I will continue with PE.

I wish that I could have been a good irrigation installer's helper for a few jobs...what I would have learned...

ktgatlin
06-04-2008, 02:39 AM
Ditto... Not sure why you'd get a hangover about small leaks in lateral line pipes. One technique we use on mains is to shut the water down at the dcva or poc. leave it off for 10 minutes. Turn it back on and if the meter needle jumps we have a small leak. No movement at all we are safe. Not a 100% perfect method but a low cost way to evaluate for leaks sometimes.

Fimco,

Thanks! This sounds cool. I will try this and see what I get.

ktgatlin
06-04-2008, 02:42 AM
1/4" spaghetti drip tubing maybe...

oops! yeah, that 1/4 in line is not poly at the hardware stores at least - I am pretty sure the black and brown line in that size is vinyl tubing.

I did find a 1/4 PE for sale online for drip irrigation.

Stillwater
06-04-2008, 05:25 AM
I've never seen 1/4 poly. :confused:

yes it is avaiable

Stillwater
06-04-2008, 05:32 AM
We do a lot of installs "on board" our local Navy base. They require pressure testing of all piping before it can be covered. We install everything except the funny pipe and screw teflon'd plugs into the end fittings. Then use a compressor to pump it up to about 75 PSI. If it holds with no more than a 2PSI drop over 2 hours, we are good to go.

Ridiculous? Of course. But that's the military for you.

No it is not ridiculous, Mil bases are self contained city's with their own police force, fire department, hospital ect. they are independent from the state they reside in. the water code is strict because of their fire fighting standards.