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jcom
05-02-2006, 09:49 PM
We were wrapping up an install and we ran into a major snafu! Zone would run for no apparent reason. All regular connections were correct and tech said his connects were right at the valves. We ruled out electrical malfunction after checks. Only viable choice had a mainline connected to the output of a Hunter PGV valve. Valve would allow full flow in the reverse direction as if it were unrestricted. We rerouted mainline to proper connection and everything worked as planned.

Question is do all valves allow for full flow in the reverse direction?

John:nono:

Dirty Water
05-02-2006, 09:51 PM
Diaphram valves will allow for full flow in reverse.

jcom
05-02-2006, 09:58 PM
Many thanks, DW . Our first time with this particular snafu.

John:dancing:

Dirty Water
05-02-2006, 10:08 PM
Many thanks, DW . Our first time with this particular snafu.

John:dancing:

Zone valve was installed in reverse? I've never done that, but I have accidently crossconnected a zone with the mainline :)

jcom
05-02-2006, 10:14 PM
Surprising that one with so much knowledge is not "wearing" the cheese head and Green Bay logo.

But alas, all is not a perfect world. (Or was that another advertisement).

John :confused:

Dirty Water
05-02-2006, 11:13 PM
Surprising that one with so much knowledge is not "wearing" the cheese head and Green Bay logo.

But alas, all is not a perfect world. (Or was that another advertisement).

John :confused:

I have to stay true to my local team :) Besides, they will be at the bowl again next year... :)

Wet_Boots
05-03-2006, 07:47 AM
There are diaphragm valves that will restrict backwards flow, but those are the process control type of valves. Those will have a top chamber that is isolated from the inlet/outlet portion of the valve, except through an outside tubing connection between the two. Put a small check valve in that tubing connection, and you have a diaphragm valve that will restrict reverse flow.