Master valve wont turn off

I have recently purchased a Rachio Gen 2 and am having an issue. Everything is wired up and seems to be working. I have a master valve set up at the tap to stop leaks throughout the system when not in use.

The issue is, when a zone turns on, it successfully turns the master and zone valve on and watering starts. However when the zone is scheduled to stop, the zone valve turns off ok, however the master valve does not turn off. It never turns off, and the system keeps leaking. The only way to turn off the master valve is to restart the entire Rachio unit.

What do I need to do to ensure the master valve also turns off when no zones are running?

What kind of master valve do you have? Plastic or brass? Hopefully it is inline. Have you checked the tuning on the valve? Tuning is done for shutdown purposes. The round handle or the X top on the flow control should not be all the way out.

Back it all the way out and then return it about 2 full turns on a Superior brass valve, 2 1/2 turns on a Rainbird brass and @3 turns on plastic inline valves.

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I just installed a controller. The M terminal is always ON (24 volts). Master Valve is selected in the setup. Why is it always ON? Kind’a defeat the purpose of a master valve :slight_smile:

May I ask, did you have to replace a power supply, perhaps to support 220V voltage? In case you’ve used a DC power supply, which are more common, Rachio will be unable to turn off the output.

No, it’s the original PS, it’s a new unit I justly bought from Amazon.
Rachio seems to think it’s just defective. Thanks for the input though.

Yes, I did buy a new power supply because I’m in Australia and needed 240V.

Why would this matter? Is there any way around this?

As long as what you’ve bought is 24 volt AC power supply, with 1 to 1.5 Amp rating, it should not matter. Be careful since a more common DC power supplies will not work.

The Rachio will power ON with the DC supply, and even allow a zone to be turned ON, but without a period of zero crossing (whereas voltage is 0 volts), a zone will be unable to be turned off.

Even if Rachio could have been made to be compatible with a pure DC supply, DC voltage is not good for driving irrigation valves as solenoids within will heat up and quickly burn out.

@MDNZ was able to source a compatible supply from jaycar:

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