Master Valve only on specific zones

I only need my master valve to be active for a few of my stations, not all. Would be nice to be able to select that feature for each station instead of the whole timer. This’ll be helpful for me. Thanks for a great product!

A deeper discussion of the master valve function is appropriate. A master valve function can have different applications:

  1. It can be used as main valve to prevent uncontrolled water flow in case a zone valve malfunctions and becomes stuck in the open position.

  2. It can be used to activate a pump relay for those who use well water.

  3. It can be used to selectively activate a fertilizer injector by zone. This allows variations in “fertigation” based on zone and plant types. In this application, the master valve function controls a valve to open or close the fertilizer suction line.

Most residential irrigation controllers do not have a master valve by zone feature (i.e. application #3) and only concentrate on applications #1 and #2. Application #3 is generally found on better professional level controllers.

I hope to see Rachio offer a master valve by zone feature. Better yet, I hope to see the capability to have more than just one master valve. For example my front yard has a valve set manifold and my back side has another valve set manifold. Each manifold requires its own independent master valve. I like to see each zone being able to selectively enable either MV1, MV2, MV3, etc. This is a wish list of functions that I’d like Rachio to seriously consider for future software upgrades.


@jstew4880‌ @peacock‌ Definitely plan on doing this, fortunately ‘master valve by zone’ is just a software change. For more than one master valve, would you need new physical connections on the backplate for multiple master valves?

Franz, yes, to make the multiple master valves feature work, it would require a separate physical connection for each master valve. Maybe my impression has been muddled by other wifi-based controller brands I have been evaluating, but I have been under the impression that each ordinary (non-master valve) zone can be programmed to act as a master valve. If that’s the case, then realistically you’d just need to make a fairly simple software change to allow: 1) a master valve by zone feature and 2) multiple master valves to be designated. It would then be up to the user to designate which connection would be a master valve zone.

@peacock‌ Ok makes sense, that’s kind of what I thought. The first change isn’t that hard, the second change gets harder. I can promise the first change is in our backlog, the second change might be too much work to make the cut. Thanks for the feedback!

In my particular application, I’ll only be using the MV output to turn on a fertilizer controller valve. Since I have two fertilizer injectors, one in the front yard and one in the back yard, I can use the same master valve output to energize both fertilizer intake valves. The problem with this setup is it would require the Iro’s MV output to drive TWO master valves simultaneously, in addition to a zone irrigation valve. Can the Iro handle this much current?

@peacock‌ We support one valve per output. Hooking up two would draw twice the current threw that hookup. If there’s a situation where there are two other zone valves on at the same time and two master valves are on, you’ll blow the fuse. I wouldn’t do it or suggest it :slight_smile: We are UL certified for up to 3 zones. Thanks and have a great weekend.

I have a similar situation. I am using the blue terminal to operate a pump relay but only a few of my zones are supplied by the pump, the rest have a separate source. I would like to see a software update to allow the option for each zone to either energize or not energize the blue terminal.

What about setting the master valve to the individual watering schedules instead? Than you can set a schedule with or without the master.

Yes, if I had the ability to choose wether or not the master valve terminal was energized per watering schedule then that would solve my problem.

What is the rated current for each output or device total? I am thinking of adding a small relay in parallel to the valve for the zones that I want to run my pump for. The relay would be a switch in the pump start circuit that would close only when that particular zone was active. The current draw of the relay would be less than an additional valve, approximately 0.1 amp. Three devices would be operating simultaneously: valve, pump relay and the added relay.

The Iro is rated for 0.3A inrush current per zone and 0.23A constant current per zone. As Franz mentioned, the hardware is capable of running up to 3 zones concurrently.

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The blue wire is for the pump start, it is wired through the normally closed contacts of each relay in series. There is one relay connected to each drip zone so when the zone is active it breaks the circuit to the pump.


Can you please give me the information on the relays you used.

URBEST®HH52P AC 24V Coil DPDT 8 Pins Electromagnetic Power Relay w DYF08A Base

I measured the current drawn by this relay at 0.077 A

Any idea when/ if a single master valve on/ off by zone will be coming out. This would be very helpful for me.

I don’t have a time frame for this feature at the moment. Will post when this is being worked on.


I’ve been waiting this feature for a while as it’s quite important to me. Is there any progress on this? Or do you have any updated time frame?

@jleeca, it is on our list but I don’t have an update. We’re upgrading our backend systems that should allow for this in the future, but I don’t have an updated time frame. Thanks for checking in!