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My installer showed up a couple of weeks ago and replaced all of the Weathermatic valves with Hunter valves. I had time to cycle it 2 or 3 times and it worked great. I guess the real test will be next summer.
I had sent him a "to the point" letter and attached a print of the threads from this forum. He showed it to his supplier and got "about $300.00 worth of free stuff", (I guess including my new valves).
"Thank you" to this forum and the nice people in it.
[QUOTE=Sprinkus]Two things I would check at this point are the gauge of wiring that was run to the valves and the water pressure to the system.
Undersized wiring to the valves can cause this type of problem as well as excessive pressure at the valves.
16 gauge wire should be the minimum wire size for a small residential irrigation system, if the contractor used 18 gauge or smaller wire then there may be enough of a voltage drop when the solenoid is operating to cause damage to the solenoid.
Excessive water pressure at the valve will cause the solenoid to have to work harder to open, the increased amperage required to operate the solenoid can also cause damage to the solenoid.[/QUOTE
Although the voltage drop may not be the only problem with the Weathermatic valves, I certainly agree with the concept of the gauge wire being too small for the length used. I would only add that the gauge must be decreased (larger wire) as the length is increased between the controller and the valve solenoid. The key is to measure the voltage across the solenoid, as close to the solenoid as possible, while energized. Then measure the voltage at the output of the controller while energizing that same solenoid. The difference between the voltage at the controller and the voltage at the solenoid is the "voltage drop" or loss due to the length and gauge of wire. A 5% voltage drop MAY be tolerable (check with valve mfgr), but the less drop, the more powerful the solenoid action will be. To be told to use any particular gauge wire with no consideration of length is ridiculous, but is a common mistake made by many installers, system designers and, sorry to say, even some EE's. EXAMPLE: 18 gauge copper wire, at 20 degrees C, has a resistance of 6.385 ohms per 1000 feet. That means that in a distance of 500 feet (2 wires = 1000 ft) from controller to valve, using a 20 ohm solenoid that your voltage drop will be, simplistically, [(6.385 ohns/20ohms)(24 volts)] = 7.662 volts, or about 32% (7.662volts/24volts)..... way toooo much! I realize that a 500 foot run is likely not too common, but just use the same math for any distance you may have using 18 gauge wire. If that 32% is not reduced to less than the mfgr's specification for adequate operating voltage AT THE SOLENOID (not at the controller), then you will have to increase the size (decrease the gauge) of the wire or some how increase the voltage at the controller for only the high resistance (long) wire runs. 16 gauge copper wire is 4.016 ohms/ft and 20 gauge is 10.15 ohms/ft, both at 20 degrees C. Hope this helps.
Although the voltage drop may not be the only problem with the Weathermatic valves, I certainly agree with the concept of the gauge wire being too small for the length used. I would only add that the gauge must be decreased (larger wire) as the length is increased between the controller and the valve solenoid. The key is to measure the voltage across the solenoid, as close to the solenoid as possible, while energized. Then measure the voltage at the output of the controller while energizing that same solenoid. The difference between the voltage at the controller and the voltage at the solenoid is the "voltage drop" or loss due to the length and gauge of wire. A 5% voltage drop MAY be tolerable (check with valve mfgr), but the less drop, the more powerful the solenoid action will be. To be told to use any particular gauge wire with no consideration of length is ridiculous, but is a common mistake made by many installers, system designers and, sorry to say, even some EE's. EXAMPLE: 18 gauge copper wire, at 20 degrees C, has a resistance of 6.385 ohms per 1000 feet. That means that in a distance of 500 feet (2 wires = 1000 ft) from controller to valve, using a 20 ohm solenoid that your voltage drop will be, simplistically, [(6.385 ohns/20ohms)(24 volts)] = 7.662 volts, or about 32% (7.662volts/24volts)..... way toooo much! I realize that a 500 foot run is likely not too common, but just use the same math for any distance you may have using 18 gauge wire. If that 32% is not reduced to less than the mfgr's specification for adequate operating voltage AT THE SOLENOID (not at the controller), then you will have to increase the size (decrease the gauge) of the wire or some how increase the voltage at the controller for only the high resistance (long) wire runs. 16 gauge copper wire is 4.016 ohms/ft and 20 gauge is 10.15 ohms/ft, both at 20 degrees C. Hope this helps
Just an update....been running with the "Hunter" valves for two months and not a single failure....I'm not sure what the problem was, but replacing the Weathermatic with Hunter seems to have fixed it.
The Weathermatic company went through some struggles after their founder died, so figure their solenoid woes as one indication of this. Supposedly, the solenoid failures were connected with accumulated hours of valve operation, which made for some confusion, as valves in areas with wet weather, and reduced hours of operation, weren't seeing the failures that other parts of the country were.
Their valves were always considered to be among the best, before this problem cropped up. Too bad, since they'll be awhile living this one down.
I must have gotten into the WM valves after the problems in 03. Only solenoid failures have been on the 'Silver Bullet' economy type valves.
Please don't take this as gospel as far as WM valves being the best out there, they all have problems.
I would never ever install a Toro valve after their debacle with the flowmatics. Ask any independent irrigation guy which valve he hates the most!
The old irritrol valves are the ones that fail in the open position, which is darn unhandy if you ask me.
I have had WM solenoids fail at my own home. Do I still put them in the ground with my name on them standing on a 5 year warranty? Yes.
Sorry to post on so late after my initial post last year.
I had an irrigation guy out last fall to replace all of my solenoids (32) at WM's expense. When he came out and saw how my system was wired, he told me that was why I was having so many problems and that he'd seen it before.
His explanation was that the wire to the solenoid (not the common, but the other) should have been 'terminated' at the valve and not connected to the ongoing lead down the line, as the common wire must be. So he clipped the one side after the solenoid on all the valves.
This seemed to have made a signficant difference. The rest of last fall was dry and I ran the system regularly without problems....
However, this spring and early summer have been excessively wet and hence I haven't had to run the system up until now. After the first week or so of use this summer, I have had two solenoids go bad on me, one that stuck with the valve shut, the other with the valve stuck open.
It's too early to tell, still, but this does not make me as comfortable as I was at the end of last season. The guy who replaced my solenoids said to call him back if I had any further problems and left me with several extra solenoids. I replaced them but have not had any success keeping the one solenoid threaded in place, so I think I'll have to have him come back out.
The saga continues....
It's been a year later and I have not had anymore solenoids fail since I performed my 'modifications'. Unfortunately, with having one of the dryest August's on record, my well gave out so even though the irrigation system is ok, I still can't water. Town water is just too expensive. :(
I actually just wanted to post a follow-up to some of this. Weathermatic actually dropped me a note in reference to my issues and here was my response:
Did I resolve the actual issue? Probably not, I fashioned up a band-aid and it keeps me happy as I don't have to come home and cringe everytime I look at the Controller as I walk through the garage.Quote:
My problems never went away, I designed a solution around it. As each zone turns on, the voltage is 24VAC. After a short time, I fold the voltage back. I haven't had a solenoid failure in over a year since doing this. I can guarantee that they will fail within days if I remove my 'solution.' Honestly, I think part of the problem lies with the fact that the irrigation company used a Hunter controller with your valves and also wired the system with non-UL approved wiring. It's difficult to keep blaming Weathermatic on the problem when it can't be completely confirmed that it is 100% of Weathermatic's issue.
Al
In case no one else is keeping track, this thread has been running since July of 2005 !!!!
By the time it gets sorted out, it might be 2015. Sad, really. amartin's modification is interesting, to lower the operating voltage of the valves. (some diodes wired in series could have done it more simply) Lower voltage would reduce the buildup of heat, which may have been a contributor to the solenoid issues.
Well, it does go a little bit farther. The controllers are intelligent and monitor current through the solenoid. Variances in voltages lead to variances in current sensed and it trips the controller showing Err on the zone. I compensated for this, but I can't give away all of my secrets ;)
What controller are you using?
Hunter Pro C.
Replaced another failed solenoid off of the same system I have had 2 other previous failures on. Looks like water got wicked into the body somehow, rust was seeping from where the wires meet the body. This was on a Weathermatic Silver Bullet valve, and had square solenoids. No failures so far on the same system with the round replacement solenoids.
This was a system installed 3 years ago.