SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

OK.. tonight when I got home.
Zone STILL not working. Opened solenoid again. Zero flow.
Shut off main valve.
Removed the new valve and it's pieces-parts.
Opened the main valve and flushed water thru the lines for about a minute.
Closed main shutoff, drained water in the zone valve and re-assembled the zone valve.
Turned on main shutoff and checked for leaks. None.
Opened solenoid .. still no flow.
Screwed solenoid back closed, then turned on zone at controller.
I got low flow, then the zone started behaving normally. YAY !!
I ran it a couple of times like that - 3+ min each and all looked and worked great. Even adjusted the head radii and coverage.
FIXED !! Looks like I had crap in the line.,

Well, no.. Not quite.
About 2 hrs later I went to run it [manually] for 15 min, and we're back to low flow.. the original symptoms. 3 or 4 repeats (off, then ran it again) with same results. LOW FLOW!!!

I guess next step (tomorrow night) is to put a voltmeter across the solenoid wiring and check voltage to see if it drops after initial switch on.
Can't think of anything else to try, other than to move wires on the controller and try running it as another zone.
I voltage looks OK, then I'm stumped...

Checked voltage to solenoid and at controller.. a firm 24VAC at both ends. Yes, solenoid is being activated.
I've called the installers out to see if they can figure it out.. Tues pm is appt.
At this juncture, I've tried everything I can thing of...

I hope they installed an upstream valve that's defective, because it doesn't make sense that I can remove the value guts on the bad zone, open the master shutoff valve and get ZERO flow without turning on the bad zone at the controller.

I'll keep y'all posted..

yes... took guts out of the valve, opened the master shutoff, NO flow to zone (open pipe where valve should be) until I manually triggered the zone from the controller.

Problem solved !!
And I feel REALLY STUPID about it. 'Cuz it was MY fault !
Cost: $157

The installers came out.. and tested stuff, checked the master valve (yes, there IS an electric one AFTER the manual shutoff and back-flow valves mentioned in my prior posts. It was buried and NOT marked on my schematic), replaced the "guts" of the new valve (with another new one - but didn't charge me for parts, that was nice), and still NOTHING.
We checked main water meter for leaks. All good. They're scratching their heads.

Then the lead guy had his partner close off one nozzle on the zone, then a 2nd, and bingo, it comes to life !!
They checked the other nozzles for leaks and replaced all the adjustable nozzles with FIXED 4-8' radii nozzles, then turned it on. All works fine. Apparently, the Hunter adjustable nozzles I had put on last year require more water pressure (to run the 11 nozzles in the zone) than the city source was supplying !!!

I never would have thought that. or known.. I learnt something.. and it cost me !!!
Oh well...
Thanks for everyone's help!