How to wire your controller - Basic and Advanced Wiring

Wiring your Rachio controller

Rachio 3, Generation 2, and Generation 1

Not sure how your irrigation system wires match up with your Rachio smart sprinkler controller? Have advanced wiring needs? We're here to help!

This article reviews instructions for basic and advanced wiring for all Rachio Smart Sprinkler Controllers - the Rachio 3, the Generation 2, and the Generation 1. Select your controller type below for targeted instructions on wiring your controller.

Basic vs. Advanced Wiring 

Wiring a sprinkler system controller is fairly straightforward and involves matching your system's wires to the correct terminals. If your system is a little more complicated, you may have more wires than zones to accommodate things like Master Valves, Pump Start Relays, and Indexing Valves. Advanced wiring requires a little extra configuration, but the instructions below will help you through most wiring situations.

Rachio 3 Generation 2Generation 1

Basic Wiring - Rachio 3

The wiring bay of the Rachio 3 includes terminals to house the common wire, wires for each zone, and advanced wiring components.

Zone Wires (1-16)

Zone wires correspond to your landscape's zones. Insert them into the blue numbered terminals. An 8-zone controller can accommodate 1-8 zone wires; a 16-zone controller can accommodate 1-16 zone wires.

Common Wire

Common wires are often labeled "C" or "Com." You can insert them into any of the white "C" terminals.

Master Valve Wiring

Not all systems have a master valve. A Master Valve is a “normally closed” valve installed at the supply point of the main line that opens whenever a zone is operating. It is normally labeled "M," "MV," or "Pump." Please note, Master Valves should only be wired to the "M" and "C" terminals.

Want to add a Master Valve?

If you have a master valve, wire it into the dark gray "M" terminal of the Rachio 3 wiring bay, then enable it within the Rachio App ("More" tab > "Controller Settings" > "Advanced Wiring (M Terminal)" > "Master Valve").

How to add wires - Rachio 3 

The improved terminals on the Rachio 3 make inserting wires a breeze - no screwdriver needed! When wires are successfully inserted into the Rachio 3 terminals, the terminal buttons will fix in an upward position. Have questions? Check out our installation guide.

Advanced Wiring - Rachio 3 

Rain and Flow Wired Sensors - S1 and S2 Terminals (optional)

You can connect up to two rain or flow sensors to your controller using terminals "S1" and "S2."

Sensor Wires - 24 VAC+/- (optional) 

The 24 VAC + and - terminals are used for extra wires from wireless sensors. These terminals replace and perform the same function as the SP and SC terminals from the Generation 2. 

  • 24 VAC + is for sensor power wires (this corresponds to the SP terminal on the Generation 2).
  • 24 VAC - is for sensor common wires (this corresponds to the SC terminal on the Generation 2). 

For more information, go to

Pump Start Relay Wiring

Pump Start Relay serves as a switch that activates 110-220VAC power to the pump when the Rachio 3 Smart Sprinkler Controller's master valve is enabled. Since the Rachio 3 controller outputs 24VAC, a pump start relay is required when using a pump with the Rachio 3.


In order to avoid potential damage from electrical interference, relays should be installed at least 15 feet away from the Rachio 3.

Want to add a Pump Start Relay?

If you have a Pump Start Relay, wire it into the dark gray "M" terminal of the Rachio 3 wiring bay, then enable the 'Well or Pump Start Relay" within the Rachio App ("More" tab > "Controller Settings" >"Advanced Wiring (M Terminal)" > "Well or Pump Start Relay").

Make sure that the total draw of the Pump Start Relay plus the draw of the valve does not exceed 1.3 amps at 24 VAC, 60 Hz. The controller does not provide main power for a pump.


We recommend using the Munro StartBox or SmartBox. Specific model recommendations below:

StartBox models

  • MPSR242W11 110 volt up to 2 Horsepower pump
  • MPSR242W22  220 volt up to 5 Horsepower pump

SmartBox models

  • MPLC242W11T 110 volt up to 2 Horsepower pump
  •  MPLC242W22T 220 volt up to 5 Horsepower pump

Indexing Valve Wiring

Indexing Valves offer a central hub to automate multiple zoned irrigation systems. Usually consisting of 1 inlet and 3+ outlets, Indexing Valves can operate on city water or pumps.

How an Indexing Valve works

An Indexing Valve will water on a zone by zone basis, diverting the water supply from one outlet to another in a rotational direction. The order of the zones cannot be changed on an Indexing Valve and are predetermined by the order in which they were installed. For more information, please see this support article.

Want to add an Indexing Valve?

If you have an Indexing Valve, wire it into the dark gray "M" terminal of the Rachio 3 wiring bay, then enable the Master Valve within the Rachio App ("More" tab > "Controller Settings" > "Advanced Wiring (M Terminal)" > "Master Valve").


If your system’s water supply comes from city water, install by following the Master Valve wiring instructions above. A pump start relay is required when using a pump with an Indexing valve.

Sharing a Wire Across Multiple Devices?

If you need to share a common wire or Master Valve wire between two Rachio 3 controllers, please click here for more information.

Rain Sensor Wiring

Rain sensors normally have a fairly basic wiring setup. If you are unsure how to set up your rain sensor with the Rachio 3, click here for further instructions.

Video - Understanding Advanced Wiring 

Video Note

Our navigation has changed within the app. To edit your advanced wiring, see the instructions below.

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