Sprinklers Don’t come on when they should

First determine if the RainDial controller “thinks” it’s turning on the valve by watching the LCD screen a valve is on.  If a small number matching the valve number appears on the top row of the screen, the controller “thinks” it has turned on that valve.

  • If you do not see the number and the LCD blinks and says off, the controller has most likely failed and there really isn’t much you can do. Simply send it to us for repair, we’ll get it back to you.
  • If you do see the number, the controller has done what it can to turn on the valve and the problem is likely due to one of the other issues described below.

When the Irritrol controller “thinks” it turned on a valve but the valve doesn’t work, there are several possible reasons.

  • The battery is good (so the display and timer appears to function), but the valves do not activate but he power is off so the valves cannot activate. Check breakers, power wiring… and the fuse.
  • Battery is good, but transformer has failed – see links on testing the transformer. There are very simple ways to check the transformer Click here.
  • Wires have broken, are disconnected, or miswired – see Check #3 in testing the rainDial Transfomer.
  • Solenoid or valve is bad – see Check #3 in testing the rainDial Transfomer
  • The controller/system has simply failed and should be sent in for repair.

Be sure to look at the other troubleshooting DIY topics related to resets and valve testing.

All material copyright Brian Keller, aka the RainDial doctor

26 thoughts on “Sprinklers Don’t come on when they should

  1. So my unit was working fine, but then I noticed that timing got mixed up (sprinklers started coming on during day instead of night). I noticed that the clock was way off and it looked like the unit kept losing power and the time got reset. The a/c plug seemed a bit loose, and I got that resolved, and the power has been consistent. However, now I noticed that the auto program didn’t seem to be running. I went through all of the stations and tested them manually to see if they worked (they did). I then tried changing the start time for the auto program so I could see if everything came on. But, only a couple of stations turned on, the rest didn’t. Is there some reason why they work on manual mode, but not automatic?

    • Hi Dan,

      With the power interruptions, I would suggest you do a full reset – see the DIY page and reprogram. It’ll have a default setting of 7am, every station, every day for 10min. so you’ll need to change that.

      Let me know if that resolves the problem, and also let me know the model number that appears near the semi-auto button.

      brian – aka the rd600 series raindialdoctor

      • Ok. So first, it’s an rd 900. The power problem wasn’t totally fixed. It is currently connected to an a/c plug, and there wasn’t a 9v battery at the time. So I did the factory reset, and changed the start time and run times to our prior settings. I then waited for the start time, and when it was speed supposed to start, the power to the unit went off and the screen was blank. I went to open the unit to see the wires, and the screen came back on. It also indicated that the first station was “running”. However the sprinklers were not on. I then stopped the cycle and changed the start time to a couple minutes ahead of the current time and turned off station one so that it would start at station 2 this time. I also attached a 9v back up battery. I waited, and the power stayed on this time, and it showed that station 2 was on, but again, no sprinklers. Seems to work on manual mode, but auto is doing nothing. Any other thoughts? Thanks in advance.

  2. When the station is supposed to come on for shrubs, it waters the grass. I cannot manually turn on the shrub station.

    • Hi Dave,

      Your RD600 is likely working if you see the display indicate the valve number that is on, on the top row of the display. If the numbers are not right, let me know.

      If they are right, you could have a wiring problem so check everything is securely in place. For the shrubs, you can try measuring voltage at the valve when you turn it on. An $10 volt meter that can measure 24VAC would easily do the job and it’s not hazardous. That would tell you if the timer and wiring are good. If all good, then the valve or solenoid is bad

      post back here with what you’ve found.
      thx, Brian – aka the RainDial Doctor for RD600, rd900 and rd1200

  3. When the sprinklers are on, the digital clock time actually slows down by 12 minutes during the hour the sprinklers are on. Also, each sprinkler station stays on a minutes or two longer than programed. So each time the sprinklers come on, they come on 12 minutes later than before. After a few weeks, the sprinklers do not come on until several hours after the initial Start Time. This makes no sense to me. The sprinkler system has been working perfectly for several years. How does a digital clock slow down?

    • Hi Ken,

      I have seen a problem where the timer runs too fast, but not usually too slow. In the past and find that it often goes away when I replace some components inside the timer. I’d suggest sending it in for repair; if I can’t get it going, we can discuss other replacement options.

      Brian – the RD600 series sprinkler timer repair doctor

  4. I just bought a new Rain dial system. I connected it exactly like the old one. When I programed the cycles and days, hit the start button, nothing happened. I could go to the sensor box and manually run the system. was wondering if it’s the sensor valve.If it is, is this something I can purchase and install myself. Thanks , Kevin

    • Hi Kevin,
      sorry for the late reply, I missed your post somehow. When you say “nothing happened” what do you mean? Did it just change to “off” or did the valves say they were coming on but no water was flowing? Let me know; I promise I’ll get back to you sooner 🙂 You can always email me, it’s faster. Just use the ContacUs menu above and fill out the information. It’ll forward it to me as an email and I’ll reply directly .
      aka – the Irritrol RainDial doctor for TD600 RD900 adn RD1200 timers

  5. Hi. I have an RD- 900

    The rotation will go on as planned and as timed. However when it gets to station number five it shows on the LCD that number five is running but there’s no water coming out. Once that’s done it goes on the six in the system and appears Who operate normally for the rest of the stations. I can manually turn the head on the yard and water it that way. I’m wondering if there’s some lead that’s not triggering station number 5 to release water evnen though it is showing on the system as that station being active

    • Hi David,

      Sorry for the late reply on this one, I missed it somehow. Try swapping wires for 5 and 6 to see if the problem follows the wire (meaning it’s probably a valve or wiring issue.) If it does not follow the wire, then just send the dial/lcd module and back terminal board in and I’ll get it repaired for you.


  6. Hi,

    I can’t figure out why my 5th valve won’t run. I have checked the connections and when everything cycles through it jumps from 4 to 6 but I only have a 5 valve setup there is no 6th valve. It’s like it’s not reading it or something. Any ideas?

    • That’s strange behavior for sure. I suspect it’s programming related, consider doing a full reset and start again. Also try using a different program, say “C”, and just program valve 5 to run. Give that a try and let me know what you find. I’m sure we can figure it out.

      Let me know if that helps,
      Brian – aka the RainDialDoctor

  7. Have you ever seen a Irritrol Raindial add hidden start times, or just start by itself ? I have a unit programmed to come on at 6:00am, which it does. It also comes on by itself at 9:30pm and it starts with zone 2, not 1. I have factory reset a couple of times in the past, and this problem comes back randomly on its own, sometimes growing to starting 4 times a day.

    • Hi Michael,

      I can’t say I’ve seen that “exact” scenario, but I do often see random behavior. I’m confident it can be repaired. Everything you need to know is on the “how to get it repaired” page. The cost typically ranges from 45 to 65 for six to twelve station models. I warranty the repair and also pay the return postage; it’s sent 2 day priority mail.

      Since you’ve already done a good job troubleshooting it with resets and other steps, I think sending it in is the way to go.
      Let me know what you decide to do,
      Brian – the Irritrol RainDial RD600, RD1200, RD900 Repair Doctor

  8. Different problem with mine, I have a RD-900 and all the valves work fine when manually started or in semi-auto, but when I program and try to turn the day on, my options are either off or —, On is not an option. Thoughts?

    • Hi Chris,
      That means you have skip days programmed. Either look at the manual under skip days, or do a factory reset and it should behave more like you’re expecting


  9. Hello, I recently noticed a problem with my sprinkler system. After noticing that the plants in the front flower bed weren’t getting any water, I manually went through each zone and determined that when I tried to activate the zone covering the front flower bed it showed to be on, on the controller but there wasn’t any water coming from the sprinklers in the front flower bed. All other zones work fine….

    • Hi Keith – Look at the sections related to “testing the transformer…” If you can determine that the transformer is good, then the controller and backboard must be at fault – just send it in for repair. Details are on the How to get it repaired page. If you have questions about any of the process, let me know.

  10. Have a rather odd situation … the controller has worked fine for years. Recently, however, it has stopped triggering valves automatically according to the schedule. BUT … I can trigger each zone individually using the controller’s manual on/off function. I’ve double and triple checked the schedule (times/watering days/etc …) but can’t figure this one out. I’m ready to replace the whole thing. Any ideas?

    • Hi David, Thanks for posting. That’s a little odd, but I have heard similar things before. As they fail, they can get a little flakey so it doesn’t really surprise me. It sounds like you’ve done a thorough job of troubleshooting it and I also believe the controller is at fault. If you can reply with the model number (e.t., rd600-R or rd600) it would be helpful.

      I would do the following:
      1) Follow the instructions on the DIY troubleshooting page to reset the controller to the factory defaults.
      2) If that doesn’t work, mail it in. (See “How to get it repaired”)
      3) if that does work, keep a close eye on it; if it gives any more signs of flakeyness – don’t give up just send it to me for repair. The repair is solid and the timers are definitely worth repairing.

      Let me know if that helps,

  11. One valve will not come on, unless it is turned on during another valve’s operation. Controller thinks it is on but does not function independently. Because of this can not work with a program.

    • Hi Michael,

      That behavior is often due to a wiring problem (although it could be a controller issue).
      I’d do this: Disconnect all the valve wires (even the ones not in question). The Connect one at a time and test it. If you find one that’s bad, try moving it’s wire to a different station (different screw terminal) and see if it still misbehaves. If it misbehaves on more than one of the controller’s stations, it’s likely a valve or wiring problem.
      Check the common wire carefully in the controller box and also double check it in the ground-valve-box.

      If it still seems like a controller issue, you can send it in and I’ll test and repair it, but I don’t think it’s likely at this point.
      Let me know what you determine.


    • Hi Brian,

      Thanks for the comment. I noticed you sent an email on the contact page too. If you’ve already looked through the comments on this page and the transformer is good, there isn’t much else to do but to send it for repair. I’m happy to help. I already replied to your contact form; if you have any other questions, just let me know.

      Thanks for posting,

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