It sounds like the system has a master valve that is working and the zone valves that are not working. When you turn the system on manual at the controller, the master valve turns on which lets the water go through the main and so the valves will run. Are you leaving the black switch (Weathermatic valve?) on? Is there enough pressure to run two zones at once?

Check the controller to see if there is a wire installed into the pump/MV port on the controller.

 

Sounds like Weathermatic valves. There were/are issues with the Weathermatic solenoids. Maybe you have solenoids that are not strong enough to pull the plunger up and open the valve. When you move that black lever, you're manually pushing the plunger up and the electromagnet then takes over and holds the valve open until the clock shuts it off. I'd be those suspicious of those solenoids. An ohm meter is your friend.

 

Thanks for the really quick replies - and the explanation makes a great deal of sense to me.
What should the ohms read? (I think we have a meter somewhere - I'm going digging)

The rest of the lawn is watered by 4 zones run by a newer Hunter controller from a different part of the building: when we blow out the whole place in fall, the compressor hooks up where the single water line (town water) comes out of the building (I think I remember a lever type shutoff just inside) and blows out all 6 zones. No idea if or where the master valve for the Toro section would be... But the two zones we are working on both work fine manually from the valves. Not enough pressure to run properly with both open at once, but fine one at a time, after we replaced two broken heads. This 2 zone area hasn't been run in 2 or 3 years, because someone from building maintenance didn't like a head spraying a walkway or something, so they ripped the power cord right out of the controller box. We couldn't get the OK to fix it then, but it rained enough to squeak through. Not this year.

 

It sounds like the system has a master valve that is working and the zone valves that are not working. When you turn the system on manual at the controller, the master valve turns on which lets the water go through the main and so the valves will run. Are you leaving the black switch (Weathermatic valve?) on? Is there enough pressure to run two zones at once?

Check the controller to see if there is a wire installed into the pump/MV port on the controller.

I'll check the controller tomorrow for a MV wire. We were turning off the black switch once the valve was tripped, which was what made it so odd: manual control from the controller didn't work until you ran outside and flipped the switch up and back down - then it ran...
This system ran fine for several years, but I'm not surprised parts are starting to fail, it has been a while since it was put in.

 

Those valves are most likely Weathermatic, not Toro.

 

What should the ohms read? (I think we have a meter somewhere - I'm going digging)

Typical reading would be 20 to 50 ohms. I've seen as high as 65, but they don't last long...

I'm usually satisfied with 30-40 ohms.

 

Found the meter; tomorrow we'll test them, and be prepared to dig up and replace the pair of valves with something different, based on the inventory of our local parts dealer (mostly Hunter I suspect)... there is one Weathermatic in the other 4-zone section, and it drives us nuts - I think I'll be glad when that one craps out.
Thanks for all of the helpful info: it stinks having a property you maintain look bed because they're too cheap: make us look like hacks, and that's not right. We try to work around these issues when we can. Really appreciate the help.

 

Figured I'd follow up with our results... tested the valves (confirmed Weathermatics), and both read around 32 Ohms, which turned our attention back to the controller box. We happened to read the volts at the valve box and it was around 5V for the line that was off, and 10-11V on the one that was on. Saw the valves are 24V and thought those readings seemed awfully low. Couldn't see anything wrong in the controller box, so took the model number and hit the 'net for the manual. (Toro Vision ll Plus). At some point I realized we'd had two transformers hanging around, both for Toro boxes - one came off a replaced controller. Checked both, and though both were 24VAC, one was 16.25VA, the other much higher (not in front of me now). The model we have is supposed to use an even higher VA than that.
Called Toro technical service at 4:45 pm on Friday and left a message. They actually call back within an hour: I am now really impressed with them - didn't expect anything 'til Monday. He explaiedn that the controller is a two stage system; 12 or 15 volts for the panel, 24 volts for the valves... I'm sure this is all ABC's to you guys, but it was news to me
Armed with the correct (or less incorrect?) transformer, went back Saturday (4th trip in 3 days), and wired the transformer in correctly - it had been removed while we were gone so building maintenance didn't try to "help" and put set the system to run. We have water!:dancing:
Not sure at this point if it was wired backwards, or the transformer output was too weak, or both, but we didn't have enough juice to open the solenoids, and now we do.
Thanks everyone for the help - not only does our system work, but I understand why, and we stopped looking at the wrong end of the problem. Plus we'll be better equipped for the next snag we encounter (hopefully)...

 

Now is a good time to recommend replacing that controller. The Vision series have had many issues. Not many of us full time service people like them. Whenever I see a problem with one, I try to replace it. If there are no problems, I leave as is.

 

Now is a good time to recommend replacing that controller. The Vision series have had many issues. Not many of us full time service people like them. Whenever I see a problem with one, I try to replace it. If there are no problems, I leave as is.

I've never seen one without a problem...