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  #1  
Old 10-27-2007, 01:15 PM
sencinia sencinia is offline
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PVB pulsates on and off

Just replaced 2 above ground 3/4" valves with 1" below ground.
Could the size be the cause? Only happens when it comes on.
Sometimes it comes on after a fews pulses. Sometimes the PVB just stays open.
Need help. First time this has happened.
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  #2  
Old 10-27-2007, 01:20 PM
irrig8r irrig8r is offline
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I've only had this happen when there isn't enough flow to keep the float open... i.e. a drip irrigation zone. Sometimes it's required running two small drip zones at once.
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  #3  
Old 10-27-2007, 03:48 PM
sencinia sencinia is offline
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Believe I solved it.
I adjusted the outlet valve on PVB to 3/4 on.
Valves open up just fine. All zones work fine also, i.e all sprayers pop up
just as before.
Can anyone explain why this works?
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  #4  
Old 10-27-2007, 04:08 PM
Kiril Kiril is offline
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Why isn't it wide open?
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  #5  
Old 10-27-2007, 04:35 PM
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Dirty Water Dirty Water is offline
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Sometimes the flow control needs to be tuned to zone at hand. I've seen it more than a few times.
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  #6  
Old 10-27-2007, 04:43 PM
Kiril Kiril is offline
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Why would you use the PVB for flow control? Why not use the valve, assuming it has flow control?
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  #7  
Old 10-27-2007, 04:47 PM
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Dirty Water Dirty Water is offline
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Quote:
Originally Posted by Kiril View Post
Why would you use the PVB for flow control? Why not use the valve, assuming it has flow control?
I was referring to the flow control on the valve.
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  #8  
Old 10-27-2007, 04:49 PM
Kiril Kiril is offline
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Ah, yes, that was what you meant by zone.

Oh btw DW, one of the developers I have done some work with got his server hacked. Got all the code if your interested in a peek.
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  #9  
Old 10-27-2007, 05:07 PM
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Dirty Water Dirty Water is offline
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Quote:
Originally Posted by Kiril View Post
Ah, yes, that was what you meant by zone.

Oh btw DW, one of the developers I have done some work with got his server hacked. Got all the code if your interested in a peek.
Amusing.

If the code base I work on were to get leaked to the public, we would have a serious public relations problem on our hands.

Let me guess, typical LAMP setup server?

They are not as bulletproof as people think.

Laugh if you want, but we run a farm of Win 2k3 servers with IIS 6.0.
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  #10  
Old 10-27-2007, 05:13 PM
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Wet_Boots Wet_Boots is offline
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Quote:
Originally Posted by sencinia View Post
Believe I solved it.
I adjusted the outlet valve on PVB to 3/4 on.
Valves open up just fine. All zones work fine also, i.e all sprayers pop up
just as before.
Can anyone explain why this works?
Closing down the outlet valve on a PVB assembly will prevent excess pressure drop in the PVB when a zone valve opens, although you probably would be better off using flow-controls on the valves for this.
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