Alternative Water Supply

So is there a way to use the sensor input to tell the controller there is an alternative water source available (such as a Rain Barrel) using say a float switch. Then when there is alternative water available one of the outputs controls a secondary master valve and the primary master valve doesn’t get turned on?

I would not say it would be a “sensor” that could do this, but rather using a float switch type of thing (as long as something exists like what I am thinking). You you have a master valve on your main water source and a pump with a pump start relay (PSR) hooked to your alternate water source. When the float is down, the circuit from the “M” (master valve) terminal on Rachio is connected through the main valve. When the float is up, the circuit from the “M” terminal is connected through the PSR. Does that make sense? Not sure if such a float exists though.

This thread may be of interest to you.

Gaaaa. external wiring…
Would be so much better to have the device natively support this.

That probably would be nice, not sure what the demand would be. I would guess it would take two master valve connections on the Rachio and change functionality of a sensor connection.


As a proportion of their customer base: Probably not much.

For us, for example, outside of anything the R3 might do, we’d need a 5,000 gallon reservoir (minimum–for one cycle), sensors or float switches to determine when there’s enough water, an 18 GPM, 60 PSI pump, and enough filtering so we wouldn’t be feeding cruft to the sprinkler heads. Then there’s the lack of municipal regulation that prohibits the collection or rain water.

I suppose if we were on municipal water the cost savings might make the expense and trouble worthwhile, but, being on a well, probably not.