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EagleLandscape
09-26-2007, 11:02 PM
Ok, so I was looking at a repair earlier tonight.

Problem: LOW/NO WATER PRESSURE AT THE VALVES.

Customer has raindial control and they have 6 stations.

Water meter is at the curb, and the backflow T's in up by the house. Unfortunately the BF is underneath mature indian hawthorne and carissa holly shrubs.

I opened the manual bleed valve (rainbird dv series) and barely anything trickled out. extremely low pressure. Also tried running manual station from the controller, it opens up, but very low pressure. Just bubbles if anything from the heads. This happens at all six stations, so I know its not a solenoid or diaphragm issue.

I did not have a pressure gauge with me, ( i know i know) but we manage a large house across the street, and this block has great pressure.

Coming out of the backflow is like 1 1/4 black (poly?). Sub division is about 16 years old.

there is not a wire in the wiring bundle at the controller for a master valve. The water meter is not spinning, so that eliminates a possible mainline leak.

UNless there is a MV, but just not a wire?

I did find a large underground hole right after the BF where it looks like there was a break in the pipe and it eroded out tons of soil. But if there was a break, the meter would still be spinning. The only way to find out what this hole leads to, is to dig up all of the mature bushes. (last option I want to mess with.)

Only thing I could think of is that there might be a gate valve right after the backflow? But heck if I know where to find it.

I'm confused? What else could be the issue?

No pressure at valves, but no leak and no master valve?

wolfpacklawn
09-27-2007, 12:09 AM
We don't use poly tubing for main lines around here but I have seen 1/2" poly get crimped off by roots.

I would check the pressure right after the backflow valve. If good pressure there then obviously the problem lies somewhere between the backflow and the valves.

Are all the valves in the same location?

Is there possibly a filter on the main line before the valves?"

Obviously that hole sound suspect.

It may be easier to run a new line to the valves than root up mature trees and bushes.

WalkGood
09-27-2007, 12:38 AM
I figure this system used to work, right?

Water pressure inside the house is good?

Any garden hose bibb spigots to check the pressure?

Is the irrigation feed pipe totally from outside the house or is the a plumbing tap inside for the irrigation? If so check to see if someone has turned down the feed valve.

I once had a low flow problem on the irrigation at a customer where it had been fine prior. Inside the house, all faucets worked fine. After checking everything outside, they finally let me in the basement to check the ball valve for the irrigation.

As they both hubby n wife stated, that valve was full open. But the whole house water main gate valve was cranked down big time. Seems they had shut it off to fix a faucet, didnt turn it back open all the way. Faucets seemed fine since they were all low-flow anyway.

Happy hunting!

FIMCO-MEISTER
09-27-2007, 07:15 AM
You checked to make sure the meter is open all the way? If it is from what you've posted getting to that DCVA seems like the only best next option.

bobw
09-27-2007, 08:56 AM
Do you suppose that when they repaired the leak at the BF, they let some large rocks into the line and that those are hung up in the pipe blocking your flow?

Kiril
09-27-2007, 08:56 AM
We don't use poly tubing for main lines around here but I have seen 1/2" poly get crimped off by roots

Funny you should mention this. I went out on a no flow call last week and found the 1/2 poly had been pinched, not by a root directly, but by a staple that had been pulled down by a root. It had completely pinched off the line.

turfnh2oman
09-27-2007, 09:38 AM
Start from scratch. Go to the source or closest point [preferably at meter side of backflow] and check pressure. Next check pressure at mainline side of backflow. If that all checks out okay then proceed downstream [mainline]. Sounds like you have a valve somewhere in the mainline [probably closer to backflow] and probably that previous hole you don't want to dig up will reveal at least something. Meter won't spin if leak is after main valve until it opens and a zone is on. Only other option is a restriction in the line somewhere especially if all zone valves are acting the same.

Mike Leary
09-27-2007, 10:34 AM
I'd look at the DCVA..a check spring may have broken or the check itself
may have stuck closed.....do your purveyors not spec yearly testing on
backflow assemblies?

PurpHaze
09-27-2007, 11:17 AM
I personally love sitches like this as it brings out the detective skills. Sounds to me that there's a problem at/near the backflow device. You'll need to check GPM/PSI before/after it to further chase the problem.

Oh... and one more thing... examine the sitch a little more closely with an open mind. Often we run into situations where it's a combination of problems. Don't go in with a narrow mind thinking it's only one problem or you run the risk of missing something.

EagleLandscape
09-27-2007, 11:30 AM
I need to take pressure reading off of hose bib. thats for sure.
my gauge was in my other truck when i went to check out the issue.

I would love to just dig up the mainline between the dcva and the first valve but it goes under a 15' driveway and through 10year shrubs.

we'll see.

PurpHaze
09-27-2007, 11:38 AM
Take pictures and keep us updated. We love irrigation mysteries.

Mike Leary
09-27-2007, 11:53 AM
Purples point is well taken..many times I would show up at a "problem" that
had the crew vexed & solved it..not 'cause I'm smarter..but farther away from
the "percieved" cause. It's like pruning..gotta stand back & look at the whole
picture. Sometimes leaving the site alone for a few days while you post/think
works too!

Critical Care
09-27-2007, 11:58 AM
My idea on this...

If the house has good pressure at the hose bibs, or for taking showers, flushing toilets, etc., then the problem would be in the irrigation line after the POC into the homes main service line.

The DCVA could have either the input or output ball valves partially or fully closed. Or, as mentioned, there could be a hidden main valve on the irrigation line, which would probably be between the backflow and the POC into the home's main service line. If there is a leak after the DCVA, which caused the washed out area, then someone would have shut a valve off on the DCVA, or on some other main valve upstream from it. Right?

Mike Leary
09-27-2007, 03:48 PM
Is Richardson Texas a sister city of Suffock County?

FIMCO-MEISTER
09-27-2007, 04:19 PM
Is Richardson Texas a sister city of Suffock County?

Not quite. We require backflow inspections, permits, and have some active city guys. At one time we were a boom town and a lot got done under the radar.

Mike Leary
09-27-2007, 05:01 PM
have some active city guys. .

::backs out of thread::

FIMCO-MEISTER
09-28-2007, 07:55 AM
I'd look at the DCVA..a check spring may have broken or the check itself
may have stuck closed.....do your purveyors not spec yearly testing on
backflow assemblies?

No yearly testing on residentials here Mike. Just the intial install inspection. Backflows are kind of twisted logic to me. Inspect brand new ones but don't inspect older ones. What city is this in John?

FIMCO-MEISTER
09-28-2007, 08:00 AM
Purples point is well taken..many times I would show up at a "problem" that
had the crew vexed & solved it..not 'cause I'm smarter..but farther away from
the "percieved" cause. It's like pruning..gotta stand back & look at the whole
picture. Sometimes leaving the site alone for a few days while you post/think
works too!

Also helps to develop a flow chart way of thinking. Sometimes we avoid the obvious because we see the work involved and try to come up with any other solution. If the DCVA is the problem it may be cheaper to abandon that one, not disturb the landscape, tie in a new one. The goal is to fix the problem not solve the mystery.

Kiril
09-28-2007, 08:29 AM
Trouble shooting is what makes this job worthwhile.

PurpHaze
09-28-2007, 10:24 AM
The goal is to fix the problem not solve the mystery.

I have to respectfully disagree with my Texas brethren. Solving the mystery can go a long way towards self education. Sure... you can just fix a problem and move along... but understanding how/why the problem occurred in the first place helps both the immediate customer for down-the-road repairs/tweaks and the irrigator gets to file away a juicy tidbit in his gray matter computer for future situations. :)

EagleLandscape
09-28-2007, 04:04 PM
city of dallas. by frankford and the tollway. actually i think the poly material is on the meter side. i misread the figure of the backflow and never looked at the flow arrows. but im gonna try and tackle it on tuesday or something, the whole yard is already dead, so a few days wont hurt.

FIMCO-MEISTER
09-28-2007, 07:46 PM
I have to respectfully disagree with my Texas brethren. Solving the mystery can go a long way towards self education. Sure... you can just fix a problem and move along... but understanding how/why the problem occurred in the first place helps both the immediate customer for down-the-road repairs/tweaks and the irrigator gets to file away a juicy tidbit in his gray matter computer for future situations. :)

Let me change that then . The goal is to solve the problem in a long term way at minimum cost to the customer. I have a rule that I make Henry follow. If you are trying to learn that's fine but don't bill the customer for it.

Mike Leary
09-28-2007, 08:10 PM
Let me change that then . The goal is to solve the problem in a long term way at minimum cost to the customer. I have a rule that I make Henry follow. If you are trying to learn that's fine but don't bill the customer for it.

In your freakin' dreams..no employee will ever say, "I messed up this manifold
& spent the rest of the day trying to phoney it up & did not bill for it".
Unless you send a journeyman on a call..expect problems.

FIMCO-MEISTER
09-28-2007, 08:15 PM
If you can look the customer in the face and hand them the bill without flenching or feeling pains of guilt then the bill is fair.

Kiril
09-29-2007, 12:41 AM
Let me change that then . The goal is to solve the problem in a long term way at minimum cost to the customer. I have a rule that I make Henry follow. If you are trying to learn that's fine but don't bill the customer for it.

Ditto. :clapping: You can still charge, just not a premium rate. This is why laborers get paid crap and journeyman make the bucks.

PurpHaze
09-29-2007, 12:20 PM
If you can look the customer in the face and hand them the bill without flenching or feeling pains of guilt then the bill is fair.

I often have teachers, managers, administrators, etc. ask me if I do side jobs as they'd like to have their systems looked at. My pat response is, "You can't afford me." If I WERE to take a look at their systems it would be a comprehensive examination and I'd have no problem submitting the proper (and expensive) bill. :)

I'll turn them onto Leo or Louie who will do a great job for them.

Mike Leary
09-29-2007, 04:27 PM
I'll turn them onto Leo or Louie who will do a great job for them.

Who are licensed, bonded & insured, I take it?:nono: