In several conversations, including one that I initiated, the use of a 3-way switch is recommended to override the Rachio system and turn on a pump.
In my system, I have a well and a pump start relay. I have a 3-way switch mounted at my spigot so that I can locally turn on the well without having to pull out my phone every time. Previously, my Rachio 2 fed the 3-way with the M terminal and the SC terminal as an override. The common on the 3-way switch is wired to the 24V input on the pump start relay.
My question is:
On the Rachio 3, what is the best override signal? I could use S2, or 24V+. Will any of these work even though the pump start relay is fed with a common and not the 24V-?
I will eventually install the new Rachio flow meter (still waiting for the shipment), presumably to S1 and 24V-.