@Justonma - without looking at the wire bundle heading out to the valves and going default wire colors, I’d move the white wire to a Rachio C(ommon) port. If it is desired to include the rain sensor in the Rachio configuration then I’d put the gray wire in the Rachio SC (Sensor Common) port and the black wire in a SP (Sensor Power - but it is actually not) port.
Hi @Justonma, RS is actually a “sense” input. It allows Hunter to essentially listen for when your rain sensor is active.
I agree with @DLane, looks like white is your “Common” and Black / Gray are your rain sensor wires so follow his advice and your should be good.
If you wish to verify everything prior to making a switch. I recommend you connect the white cable to your C terminal (where the gray one is connected now), this should allow you to run the zone(s) with Black / Gray wires disconnected.