No Pressure to Station

[Lawns of Distinction]

Have a customer w/ 8 popups on one 3/4" valve...used to work excellent. All of the sudden they have dead spots and the popups only come up about 1/2 way...and a couple spit and spudder with very little pressure. I cannot find a leak anywhere. Blew out all the lines....no obstructions. Unscrew jartop valve and turn on water...plenty of pressure out of flow side.

Any ideas as to how to find the problem? I'm absolutely stumped. Let water run 20 minutes or so, no soggy spots...cannot find anything.

Thanks

[EagleLandscape]

Diaphragm could have gone bad inside the valve.

replace the entire valve and see if that fixes it.

[DanaMac]

trees in the area? Roots grow and choke the pipe.

[AI Inc]

ya can always dig just before the first head anc cut the pipe. See what ya have for water there.

[Wet_Boots]

No pressure measurements? Check what other zones are running at, both pressure and flow?

[Kiril]

No pressure measurements? Check what other zones are running at, both pressure and flow?

What is the point Boots? If it was working before, now it is not, what is a pressure reading on the zone going to tell you? Most all sites have more than 1 zone valve, so I think it is safe to assume here that it is only happening on this zone.

[Wet_Boots]

Never assume. Let the OP affirm that all the other zones are performing properly, and that he knows what the proper supply pressure is when the zone is operating.

[Kiril]

Never assume. Let the OP affirm that all the other zones are performing properly, and that he knows what the proper supply pressure is when the zone is operating.

Waste-o-time and clients money.

Hey, lets measure the pressure at the valve, then measure the pressure at a sprinkler. And this will tell me something I don't already know how?

[Wet_Boots]

Supply pressure readings will determine whether all-over low performance in one particular zone is due to a break or a flow restriction.

[Kiril]

Supply pressure readings will determine whether all-over low performance in one particular zone is due to a break or a flow restriction.

Both possibilities with cause lower pressure. Once again, what have you learned?

[Wet_Boots]

You reading from the Book of Dumbass again? A restriction between supply and heads results in poor head performance with a supply pressure reading that's higher than normal, and a broken line will result in a supply pressure reading that's lower than normal.

[Kiril]

You reading from the Book of Dumbass again? A restriction between supply and heads results in poor head performance with a supply pressure reading that's higher than normal, and a broken line will result in a supply pressure reading that's lower than normal.

B.S.

I suggest you look up how a differential pressure flow meter works then because one of the major drawbacks is the "permanent pressure loss due to the pipe constriction"

http://books.google.com/books?id=7FDbB7VjxkQC&pg=PT291&lpg=PT291

(referenced provided so you will shutup)

In fact this is true for any inline constriction.

Want to go over some flow and pressure equations? Perhaps you would like to finally breakout your infamous 3 variable equation that can magically solve all flow and pressure problems.

Clean off your Boots, Boots, and go back to school.

[Wet_Boots]

Oh please, don't be an a$$hole. If a zone valve fails to fully open, or tree roots close off a zone line, the flow becomes less than normal, and the pressure loss through the system becomes less. This can be observed with a pressure gauge. This is especially obvious on systems fed from homes with water meters in the basement, because of the losses in the supply line from street to house.

[Kiril]

Gee Boots, the OP already observed this without a pressure reading. So once again, what information is a pressure reading going to give the OP to help him find the problem? Perhaps he can cut in a tee before and after the valve so he can take a pressure readings to determine if the diaphragm is defective or not. Or perhaps he can simple replace the diaphragm (or the entire valve) to rule out that possibility, which would be the faster and cheaper route.

Once you rule out the valve, the next step (as has been suggested by many on this forum, including you) is to cap the sprinklers to see if you can pinpoint a break.

Stop making suggestions that are nothing but a waste of time and money.

[Wet_Boots]

No, the OP noticed reduced head performance. He did not specify the flow being either more than normal or less than normal. It almost certainly is a problem with a zone valve.

If you saw a zone of rotors operating with 35 psi at the heads, and other zones with the same number of identical heads are operating at 55 psi, and there was no visible leak, it wouldn't occur to you to take a pressure reading at the system POC?

[AI Inc]

May be a valve , but lets face it , how ofton does one deal with a valve not opening all the way? Not closing all the way a weekly thing , not opening ? once a yr maybe.

[Wet_Boots]

A valve that only opens partially can be a real mindbender the first time you encounter one. Especially when you take it apart and find no faulty parts.

[AI Inc]

True , but not as common as other probs, hence , probaly not the problem.

[Wet_Boots]

I wonder what brand of 3/4" valve it is. Toro? Hate those stoopid things.

[AI Inc]

Usualy when I see them around here it means " homeowner install"

[Kiril]

No, the OP noticed reduced head performance. He did not specify the flow being either more than normal or less than normal. It almost certainly is a problem with a zone valve.

This is what the OP noticed.

Have a customer w/ 8 popups on one 3/4" valve...used to work excellent. All of the sudden they have dead spots and the popups only come up about 1/2 way...and a couple spit and spudder with very little pressure.

Don't know about you Bootsies, but spit and spudder does NOT indicate full flow. Keep your eye on the ball buddy boy.

If you saw a zone of rotors operating with 35 psi at the heads, and other zones with the same number of identical heads are operating at 55 psi, and there was no visible leak, it wouldn't occur to you to take a pressure reading at the system POC?

Keep on flailing about Boots, it is comical to watch.

[Wet_Boots]

I guess you have never had a leak over a drainage field that soaked up every last drop of water that hit it, giving no surface indication of its existence.

[Wet_Boots]

Usually when I see them around here it means " homeowner install"I don't think they were ever really cheap enough to have appealed to the trade, but you never know with the guys who want to scrimp on valve boxes :)

[Mike Leary]

it is comical to watch.

Yes, you are.:p

[mitchgo]

I'm surprised no one has told him to get to the meter and verify flow.


To me it sounds like pipe break and or broken marlex with a drain nearby. Most of the heads are working half way except a couple spit and spudder. Let me guess.. those heads that are spuddering are in line with eachother?? Indicating that the break is in the first / and or last/ vicinicty of those heads.

Check your obvious things first..

Valve/ flow control

check your meter for flow... Is it moving like bat out of hell or hardly spinning?

If it's hardly spinning I would suggest a valve replacement, however, this may not solve the issue just yet.
It may be a clogged/ kinked pipe.

If it's spinning like a bat out of hell. You need to nozzle down all the heads and or /cap heads.. turn the zone on and verify flow.

You guys are having a B*tch fight on more detailed items rather then checking the obvious / common item things first??

[Wet_Boots]

If the valve has a flow control, it could be used to help diagnose the problem.

I figure with 3/4" valves, a wipeout break would make for a noisy valve.

[EagleLandscape]

get a room you two

[Lawns of Distinction]

Thanks for the responses...still thinking...but 3/4" Rainbird Antisiphon valve. When you take the cap off the flow side, the flow coming out (without measuring w/ a guage of any sort) will blow your head off...must be something downstream. Shy of digging up and following pipe I'm baffled. It does have those POS toro flexible pipes coming out of the hardline PVC....have seen those come loose at the fittings before but dont see any soggy areas.

[mitchgo]

Does the valve look like this?

When you turn the zone on do you hear water restriction at the valve?

If the valve looks like that, my guess is someone messed with the flow control with out knowing it.

[Wet_Boots]

There have been issues with those valves before. If you had another diaphragm assemply, with the center cut out, you could switch it with the existing diaphragm, and see what the zone does when you turn the water back on.

If they are those old ones, as pictured, consider ripping them out and installing Irritrol 2711APR valves.

[mitchgo]

Scratch that, I didn't fully read your post.

Blah.. It's a pipe break..

Kinked pipes are over time, not just all of a sudden

However, a clogged pipe can happen from debris inside the line

[Lawns of Distinction]

Mitchgo...thanks for the pic...the valve in question is Rainbird DAS-075, but the flow control is wide open....

[Tom Tom]

You said pop-ups?

Have you tried shutting all the heads off via the screw at the nozzle and then turning on the valve?

[Wet_Boots]

So what happens when you switch assemblies with the next valve over?

[Lawns of Distinction]

Tom Tom - nothing out of the ordinary....when you screw all the nozzles down you get no water but dont see anything else happening as a result.

Wetboots...havent tried switching assemblies yet only because the pressure coming out of the valve on the outflow side seems very good. I figured it was in the yard somewhere...will try that though.

I figured there was a smart way to find it...you guys have me on the right track, but I've been baffled by this for a week or so....just waiting to see a soggy spot!

[Kiril]

I'm surprised no one has told him to get to the meter and verify flow.

This might work to identify a break if you had a point of reference to compare to (i.e. knew how the ticker moved when the system was functioning properly). If the OP has a zone that is nearly identical to the one in question, and it is functioning properly, then he might use that to generate a rough reference point.

Don't know where the OP is in NorCal, but cutoff risers are real popular round here, and a split riser will impact performance of the entire zone especially if it was designed at the edge to begin with.

You guys are having a B*tch fight on more detailed items rather then checking the obvious / common item things first??

We were having a point of contention because Boots was making stoopid suggestions.

[DanaMac]

Tom Tom - nothing out of the ordinary....when you screw all the nozzles down you get no water but dont see anything else happening as a result.

Then you need to do it again, and LISTEN this time. If you turn the heads off, and no water comes out, you need to listen at the valve or the meter, and find out if water is moving freely as it normally would. If there is minimal sound, there is a constriction - either in the valve or in the field, and not letting enough water through. If you can hear water rushing through, then there is a leak.

Use senses other than sight. I've also used bare feet in finding a leak. Cooler water indicates being closer to the leak, when an area is drenched and water is flooding an area.

[Wet_Boots]

My suggestion for the OP, now that he has revealed that water is flowing through the valve, is to shut off everything downstream, and to check for leaks. If nothing shows, confirm that water is not flowing. Then you can disconnect the head nearest to the valve, and connect a garden hose to the riser, and push water back towards the valve, which now has the vacuum-breaker bonnet and guts removed.

[Kiril]

now that he has revealed that water is flowing through the valve

He revealed that in post #1

is to shut off everything downstream, and to check for leaks. If nothing shows, confirm that water is not flowing.

Suggestion already been made 3 times, but thanks for repeating it one more time.

Then you can disconnect the head nearest to the valve, and connect a garden hose to the riser, and push water back towards the valve, which now has the vacuum-breaker bonnet and guts removed.

What information will this provide so the OP knows exactly why he is doing this?

[Wet_Boots]

He didn't explain that he was running water through an antisyphon valve and observing water at the vacuum breaker. I congratulate you on your superior ESP.

Obviously, the hose dealie is to blow back debris to the valve. Beats digging up the yard. If the valve opens,fully, but water isn't flowing in quantity to any of the heads, there is an obstruction between the valve and the first head.

[DanaMac]

Kiril - now you're just an instigator, thriving off the drama.

You two are making a mockery of this fine establishment. ;)

[Wet_Boots]

It's like a mystery novel, with a new fact revealed about once a day.

[Kiril]

He didn't explain that he was running water through an antisyphon valve and observing water at the vacuum breaker. I congratulate you on your superior ESP.

He has stated it 3 times.

Post #1

Unscrew jartop valve and turn on water...plenty of pressure out of flow side.

Post #28 (his second post in this thread)

When you take the cap off the flow side, the flow coming out (without measuring w/ a guage of any sort) will blow your head off...must be something downstream.

Post #35

havent tried switching assemblies yet only because the pressure coming out of the valve on the outflow side seems very good.

No ESP Boots, it is just simple reading.

Obviously, the hose dealie is to blow back debris to the valve. Beats digging up the yard. If the valve opens,fully, but water isn't flowing in quantity to any of the heads, there is an obstruction between the valve and the first head.

Once again, the OPs first post.

Blew out all the lines....no obstructions.

May I suggest you learn to read?

[Wet_Boots]

I will let the OP state that he blew lines in reverse, since he managed to miss a few details already, like that the valves were antisyphons. I haven't heard him detail the operation of any other zones.

Meanwhile, Kiril has a new hobby to pursue (http://www.sfgate.com/cgi-bin/article.cgi?f=/n/a/2009/09/01/national/a125543D86.DTL&type=bondage)

[Kiril]

I will let the OP state that he blew lines in reverse, since he managed to miss a few details already, like that the valves were antisyphons. I haven't heard him detail the operation of any other zones.

Why take the time to blow out the lines in reverse without first verifying there is even the possibility of an obstruction? Wouldn't it be simpler to shut off all the sprinklers, then reopen them as you move away from the valve before you go to the trouble of hooking up a hose to it? This should reveal if there is an obstruction and where it is ..... no?

And who knows, maybe the hose bibb have a vac break on it (which by code it is required to) and the first sprinkler is 75 feet away, which more likely than not means there won't be enough pressure to blow out an obstruction anyhow.

Then there is the question of how such a large obstruction got in there to begin with, but hasn't caused any problems until just recently.

Like Mitch said .... do the easy stuff first!

[1idejim]

try this, drill a 11/32 hole in the mip for the lateral, tap it with a 1/8x27ppe tap, install a schrader valve ($2.00) parts 10 mins time. add 5psi constant air pressure and walk the lateral line closing the heads as you go. if you don't see anything slowly increase pressure until you hear or see a leak. personally i would close the heads first, turn the zone on and then listen to the line with my sonoscope or stethoscope for noise before doing the above. actions speak louder than words in this case, it aint worth fighting over, you guys are not dummies!!!

[Wet_Boots]

We're bored, and will fight over anything. Take this forum with a few grains of salt.

[mitchgo]

To the OP:

When you shut off the heads did you go to the meter and verify flow??
This really distinguishes .. Or guides you to your next step in finding out what is wrong..

To Kiril:

I agree that there should be a point of reference. But I have to also think that If I saw 8 pop up sprays with most of them only popping up half way and saw the meter flying at 18GPM .. I'm gonna lean towards a break ..

[Kiril]

To the OP:

When you shut off the heads did you go to the meter and verify flow??
This really distinguishes .. Or guides you to your next step in finding out what is wrong..

To Kiril:

I agree that there should be a point of reference. But I have to also think that If I saw 8 pop up sprays with most of them only popping up half way and saw the meter flying at 18GPM .. I'm gonna lean towards a break ..

If his meters are anything like the ones in my region, there is no clear indication of GPM, hence the reason I brought it up.

[mitchgo]

I of course don't know you water meter status...

I will completely agree that we both should have said, ' verify what kind of water meter you have' So we can help you determine if your meter will help you out to verify correct flow'

However,
In my area... I work on houses that were built in the 50's to new houses of 2009 . I have seen, from my research online. Almost every kind of water meter out there for houses. Do some don't have dials or easy indicataors? Yes.. Do some not have leak detectors of anykind? Yes...
But... I full believe I can determine a correct GPM or a very close estimate of a zone usage by using the meter.

I think you could to if you wanted to.. Otherwise... What's the point of having a meter if no one can read it?


.......----

[Lawns of Distinction]

I have to say...WetBoots and Kiril, even if it takes a while to find the problem, it was worth posting to watch your banter! You guys would make for an interesting day......

I will try the listen to meter suggestion soon.

Thanks

[AI Inc]

I have to say...WetBoots and Kiril, even if it takes a while to find the problem, it was worth posting to watch your banter! You guys would make for an interesting day......

I will try the listen to meter suggestion soon.

Thanks

Dont feed the tigers !

[Wet_Boots]

I think the water is flowing into the Twilight Zone.

[HokieAg07]

Ive got a similar problem at a large HOA with 3 separate systems. Problem has arisen this year, lots of new development around this HOA causing problems. Problems are showing on large zones on all three backflows. Tested one today, had 70psi static at RPZ and dropped to 30 dynamic on a large zone. System was marginal to begin with as far as quality. Need to verify a few things first but looking like booster pumps are in order.