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

I have three zones (front lawn, back lawn, and drip). I noticed a couple of days
ago that the front lawn was getting pretty dry, so I was going to increase the run
time on the controller (temperatures 105 - 110 this past week). After I changed
the run time, I thought I would start the zone manually, and saw that the zone did
not start.

I walked over to the irrigation box in the ground, and heard the solenoid chattering,
but the valve was not opening. I turned the controller off, and I went to the valve
and opened the bleeder, and still the valve would not open.

In an effort to determine the cause of the problem (I assumed that either the
diaphram or the solenoid was the problem), I swapped the solenoid with the adjacent
valve (the other lawn zone), and turned the water back on. To my surprise, I now
had two zones that were not working.

When I opened the bleeders to start them manually, I found that zone 1 still would
not start, but zone 2 started fine. I drew the conclusion that zone 1 must have a bad
diaphram that somehow allowed water into the solenoid which made it non-functional,
and when I swapped the solenoid with the one from zone 2, it must have
made that solenoid non-functional the same way. I removed both solenoids to let them
dry out.

The next day I got a new diaphram and installed it into zone 1. The old diaphram was
breaking down and leaving black "goo" every where it touched, so I still had some
level of confidence that my diagnosis was correct, and that by changing the diaphram,
I was going to fix the problem. I turned the water back on, and to my surprise there was
no change. Neither zone 1 or zone 2 would start with the controller, and zone 2 would
start manually while zone 1 would not.

I thought it through again, and figured that what ever it was that happened to the solenoids
was not going to fix itself by drying out, and that I should replace them both. I did not have
a reasonable explanation for zone 1 not starting manually (every effort was made to ensure
there was no debris on the diaphram or in the chambers, and the port to the diaphram was
clear). I also noticed that the solenoid for zone three, although still functional, was cracked
and starting to split, so I might as well get all three. When I went to the store I also decided
to get a diaphram for zone 2.

I went back and installed my new parts thinking that by replacing the diaphrams in both of
the lawn zones, and the solenoids in all three zones, I had to have eliminated the problems,
as well as prevented a future problem in zone 3.

When I turned the water back on, I was rather disappointed to find that I now had 3 zones
that would not start with the controller, and that zone 1 would still not start manually. I
also tried to start the drip system on zone 3. I wasn't sure if it actually started because
I half heartedly checked a couple of drippers, which were dry, and dismissed it as being
some of the older drip lines which were no longer being used. After all, I didn't even
open that valve up (I thought that perhaps I was brain dead or something, and at the rate
my system was going downhill, I was better off to "not" bring in an additional variable), so
I dismissed it and put my focus onto the the fact that I now had three zones that would not
open by means of the controller.

I pulled out my meter, and disconnected the wire nuts at the valves. At the controller, I turned
on one zone at a time, and then from the valves, I measured from the common wire, to zone
wire that was active, and found that I only had about 13 VAC instead of the 24 VAC that I
was expecting to see.

I went back to the controller to see what I was sending to the valves. I verified that I had
26 VAC from the transformer / power distribution board, going into the logic board. As each
was queued, I measured the voltage at the terminals that connected the field wires, and
I saw about 13 - 14 VAC for the zone that was queued, and on the inactive zones I saw
about 12 VAC . (As I am shaking my head thinking, "Really????", "Wow!!!")

So I went back to the store and bought another controller, and with shattered confidence
I installed it. Yes, it did correct the voltage problem and the chattering solenoids, and the solenoids
responded. Zone 2 is now functional from both the bleeder and the controller, zone 1 won't
start in either fashion, but the solenoid does respond to the controller. Zone 3 does not start,
but the solenoid does respond to the controller.

I took a better look at the manual operation of zone 3, and it too, does not start with the
bleeder.

I am usually pretty good at fixing pretty much anything, and at this point my confidence is
pretty much gone, and I have been knocked down a few inches.

Reluctantly, I decided to swap out the top end of the now-functional zone 2 valve, with the
top end of the zone 1 valve (diaphram, solenoid, and lid). When I turned the water back
on, I was a little surprised to see that the problem had moved with the swap. I now had
zone 1 functional (both manually and with the controller) and now zone 2 would not respond
in either method. (Ahhh, progress)

So in an effort to split up the parts that I swapped, I left the diaphrams where they were, and
moved the lids (with solenoids) back to their original locations. When I turned the water
back on, the problem had stayed with the lid. Zone 2 is functional, and zones 1 and 3 are
not functional manually (but the solenoids respond to the controller).

Just for kicks, I swapped the tops of both non-functional valves (zones 1 and 3), and got just
what I expected. They still didn't work.

So here I am, trying to sort this all out. I have a hard time beleiving that so much could go
wrong all at once. The evidence that I am seeing suggests that even with all of the parts
I have thrown at this, that I now have two valves which, after replacing both solenoids and
one of the diaphrams, are non-functional. I am thinking that both lids are bad? The only ports
I see in them are the ports to the bleeder and the ports to the solenoid. Is there somewhere
else that I should look for debris? Is it conceivable that both lids are cracked? At the same time?
And aren't leaking? Is my next step to dig up the irrigation box and the pavers next to it, to
expose enough pipe and replace both of the valves? Is it possible to replace just the lids?

Digging up the valves is a pretty big job to take on while my confidence level is hovering
right around the zero mark. I thought that I had taken a methodical approach to this, but
I am finding myself just shaking my head. Should I call a priest to cast out the evil spirits?

Any input gladly accepted... Thanks...

The controller that I removed was: Irritrol RainDial 6 station (couldn't find the model #)
The controller that I installed is: Orbit Indoor 4 station Model 57874

I am not sure how important that is anymore since the electrical portion of the system
is apparently functioning properly since I replaced it. If I am wrong about this then please
correct me, but I was under the impression that if the valves would not operate manually,
then they would not operate from the solenoid either.

I believe, given the information that I have, that the problem lies with the valves. There
were no visable markings on the valve bodies, but after digging around on the Internet, I
believe they are Irritrol 205 series inline valves with flow control. The inlet and outlet ports
are 1", and two of the three of them immediately reduce to 3/4" on each side of the valve.

Well I replaced the top bonnets on the valves, and for good measure I also
installed new diaphrams that were specifically recommended by the manufacturer,
even though the diaphrams that I had already purchased seem to work fine in the
valve that was operational. In any case, all three zones are now working properly.

I am still having a hard time understanding what the failure was, and why there
were so many failures at the same time. In my troubleshooting experience (not
necessarily sprinklers, but in general) it is rare to have multiple un-related failures
at the same time. I say un-related because everything was working about a week earlier
when I was replacing some nozzles, and when I attacked this problem, the valve issues
(which could have been related - possible debris in the source?) don't seem to have
any relationship to the controller failure.

As far as the valve failures, I don't understand why changing the top bonnets fixed
the problem. There was nothing visibly wrong with the old ones and the ports
were clear. I guess I would just feel better if I could put my finger on something,
and say, "This is the cause". I suppose that I will just be satisfied to have everything
working though.

Thanks for helping me to understand... I really appreciate it...

Ron