Intermatic Timer Replacement

Hello, I’ve got an old intermatic timer and indexing valves. That said, pretty confused as to where to begin. I’ve seen some of the posts on replacing intermatics, but I can’t make heads or tails of my wiring. What’s the most straight forward way of installing the rachio3 given this mess? Power seems to go to the intermatic timer, and then down to a power plug, which has some kind of a plugged in low voltage transfomer/timer which has a power cord going into the ground. Hopefully the pictures help…any thoughts are greatly appreciated.

@pepcob - There’s not enough information there to give a definite answer. Here are my current best guesses:

  1. The Malibu box is probably for low voltage lights and has nothing to do with the irrigation system.

  2. Is the Intermatic a low voltage version? Is there a label inside the cover that says the output voltage (e.g. 24 VAC)?

  3. I take it there is no pump involved? What is just off the bottom of the first picture with the green fitting?

  4. I’d connect a Rachio Outdoor Enclosure to the AC power coming down the conduit and then determine if the plug below need to be power also. If so, then one might run the conduit to the plug then up to the Rachio and terminate the power there.

  5. Make sure the solenoid on the master valve in the first picture is 24 VAC. Then hook that solenoid up to Rachio C and M terminals. Then configure the Rachio app to use a Master Valve option and a Fixed Schedule (Flex schedules are incompatible with indexing valves).

  6. Ideally, replace the indexing valve with individual valves and connect those back to Rachio to run individual zones.

Good luck and welcome to the community.


Thanks @DLane appreciate the help.

  1. Ahhh, yes, that makes a ton of sense.

  2. No, no label that I can see at all

  3. That’s the actual indexing valve I believe (picture attached)…those two black cables coming off the solenoid hooked up to the two yellows from the intermatic.

  4. Makes sense, I might get an electrician to do the work if we keep the plug

  5. Is there a simple way for me to verify that it’s 24 VAC?

@pepcob - the indexing valves that I’ve seen pictures of have one pipe for each zone and then a dead spot to stop on. This looks more like a master valve that would shut off the water pressure to the sprinkler system when it is not running.

Since the solenoid connected directly to the Intermatic, I’m guessing that the time is a low voltage version (24 VAC).

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Or the best looking work ever, but I got things working just fine.

Going to punt on the index valve replacement for a bit since I’m just happy to have gotten it this far. Thx again @DLaneimage