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rainsofthouston
07-25-2012, 11:47 AM
I just had someone call me and say their neighbor just had a new irrigation system installed. Since that time the caller has been hearing his pipes rattle in his 10 yr old house in association with the neighbor's new system running. He was asking me if he should get a lawyer and who should be held accountable. Glad I'm not involved! Anyway, it raised some questions:

How does this happen? Is it just poor system design with excessive pressures? Would a check valve at the cross connection reslove this? Any input appreciated.

Wet_Boots
07-25-2012, 12:03 PM
A check valve and a pressure tank might help - check keeps the house pressure inside, and the pressure tank is a "shock absorber" - always use the two in conjunction, or else bad things can happen

rainsofthouston
07-25-2012, 12:23 PM
Thanks. And this combination would go between cross connection and backflow preventer, right?

Wet_Boots
07-25-2012, 12:39 PM
Back up a moment. Your question is about the home next door to a new sprinkler system. The sprinkler system owner can't do anything beyond closing down the flow control on zone/master valve(s)

Mike Leary
07-25-2012, 12:54 PM
www.nextag.com/water-hammer-arrestor/compare-html

Wet_Boots
07-25-2012, 01:14 PM
If it really matters, there will be more information coming. Right now, not enough.

Mike Leary
07-25-2012, 01:44 PM
Who gets to drop the bomb that the system was over zoned? :dizzy:

Wet_Boots
07-25-2012, 02:01 PM
One small advantage to the basement meters - the effects of poor design don't extend to the neighbors

txirrigation
07-25-2012, 02:03 PM
I just had someone call me and say their neighbor just had a new irrigation system installed. Since that time the caller has been hearing his pipes rattle in his 10 yr old house in association with the neighbor's new system running. He was asking me if he should get a lawyer and who should be held accountable. Glad I'm not involved! Anyway, it raised some questions:

How does this happen? Is it just poor system design with excessive pressures? Would a check valve at the cross connection reslove this? Any input appreciated.

Check valve will help... is there a pressure regulator to the house?

Sounds like you need to be working on the neighbors system.

grassman177
07-25-2012, 03:38 PM
prob poor design and too much pressure. my vote goes for the tank and check as well. not much you can do other than that i believe without serious costs, and at the neighbors to boot

Mike Leary
07-25-2012, 05:24 PM
One small advantage to the basement meters - the effects of poor design don't extend to the neighbors

So, as the neighbors are sucking the supply down and causing the hammer, it is not the sprinkler system's fault?

Wet_Boots
07-25-2012, 06:02 PM
So, as the neighbors are sucking the supply down and causing the hammer, it is not the sprinkler system's fault?I think a curbside meter feeding an oversized system could drop street pressure at startup, or maybe it is subject to banging valves, if the design is really bad.

I think the neighbor with new pipe noises has to suck it up and make sure they are 'insulated' from sudden pressure drops in the street. Expense would be on their dime.

irritation
07-25-2012, 06:09 PM
I've seen this problem several times, usually when there are two meters in the same pit. The sprinkler system is trying to flow more water than the supply will allow. The meter is going crazy and vibrating, causing the noise even to the neighbor. I've had some luck turning the ball valve down about half, it doesn't seem to effect the system.

Wet_Boots
07-25-2012, 06:27 PM
I see shared meter taps never.

irritation
07-25-2012, 06:38 PM
I see shared meter taps never.

Was fairly common 25-30 years ago but most have been done away with.

Mike Leary
07-25-2012, 06:54 PM
Expense would be on their dime.

The expense could be on the install contractor who overzoned the system.

irritation
07-25-2012, 07:15 PM
It may not be "overzoned" but when it drains down, the flow to refill the pipes causes the hammer.

Mike Leary
07-25-2012, 07:41 PM
It may not be "overzoned" but when it drains down, the flow to refill the pipes causes the hammer.

If there was any slope, that could have happened without SAMs. Also Dana's favorite "auto-drains" could have done the same thing. If you were the next door neighbor, and woke up hearing that hammer, what would you do?

DanaMac
07-25-2012, 07:52 PM
Also Dana's favorite "auto-drains" could have done the same thing.

Never said they we my favorite. I said we use them on mains and manifolds where necessary, not laterals.

Mike Leary
07-25-2012, 07:58 PM
Never said they we my favorite. I said we use them on mains and manifolds where necessary, not laterals.

What, no sense of humor now that I'm released from the mental hospital? :dizzy:

DanaMac
07-25-2012, 08:06 PM
What, no sense of humor now that I'm released from the mental hospital? :dizzy:

Never know with you. Who are you today? Jekyll or Hyde? :)

Mike Leary
07-25-2012, 08:13 PM
Never know with you. Who are you today? Jekyll or Hyde? :)

I'll know better once we get back on the road.

jbell36
07-25-2012, 09:19 PM
what exactly does over-zoned mean, too many heads on one zone? i'm trying to figure this kind of situation out too, i ran across this earlier this year...

Mike Leary
07-25-2012, 09:44 PM
what exactly does over-zoned mean, too many heads on one zone? i'm trying to figure this kind of situation out too, i ran across this earlier this year...

Yes, older, smaller water systems will vary in flow/pressure during a 24 hour period, depending on demand. We bought a data logger for a water system that was known to to have crummy psi/gpm performance and found the best time of the night to run the irrigation.

DanaMac
07-25-2012, 09:44 PM
what exactly does over-zoned mean, too many heads on one zone? i'm trying to figure this kind of situation out too, i ran across this earlier this year...

Not necessarily too many heads. Too many outgoing gallons per minute.
You could have 20 heads at 1 GPM each, equaling 20 GPM. Or you could have 20 heads with 4 GPM each, equaling 80 GPM for the zone.

grassman177
07-25-2012, 09:47 PM
i often find that the system that causes hammer the most, is one that is over stretched as far as gpm on a zone.

mitchgo
07-25-2012, 10:26 PM
Back to the OP

It really does depend on where the hammering is happening and at what point the hammering is happening ( Ie At the pressure reducing valve inside the neighbors house when the sprinkler system turns on , or all through outl the house when the system turns off... or constant noise running through the house when the system is running. ect ect)

Improper designs and high water pressure are the leading causes of hammering . There are many other scenarios

Check valves on the service line help.. Water hammer arrestors help.. Pressure Tanks help.. Pressure Reducing Valves help... But it really is site specific - All those things installed and the noise could still be happening..

I've also seen the water meter itself being extremely loud and the noise echo's through the pipe and into the house

If it's a 10 year old house the meter ' Should ' have a check valve already built into the setter

DanaMac
07-25-2012, 10:38 PM
Any time I get called out to "fix" the rattling, hammering, banging, of the pipes, I tell them it is all time and materials, and I guarantee nothing. It may stop while I change or add things, then it may start up again the next day. It can be a combination of things due to poor install, poor design, higher or lower pressure than originally, someone added onto the system and never told me, failing pressure regulator, failing water meter, wrong type of backflow valve, or just plain gremlins in the system.

jbell36
07-25-2012, 10:50 PM
Not necessarily too many heads. Too many outgoing gallons per minute.
You could have 20 heads at 1 GPM each, equaling 20 GPM. Or you could have 20 heads with 4 GPM each, equaling 80 GPM for the zone.

great way to explain it, makes perfect sense

Kiril
07-26-2012, 07:46 AM
I've seen this problem several times, usually when there are two meters in the same pit. The sprinkler system is trying to flow more water than the supply will allow. The meter is going crazy and vibrating, causing the noise even to the neighbor. I've had some luck turning the ball valve down about half, it doesn't seem to effect the system.

...... but but .... a 5/8 meter can flow 20 GPM no problem .... according to boots. :laugh: