Precision Irrigation Controller

Quick Start Guide


Precision Irrigation Controller Technical Specifications                             

Power Input: 24VAC
Environmental Sensor Input(s): Growlink TDR Soil Substrate Sensor(s)
  12 VDC Power
  3.3v Signal
Output: 24 VAC
  1 Amp Fuse Per Output
Wi-Fi & Local RF: 2.4 GHz



Remote Access - Manage and monitor your climate and substrate remotely and quickly adjust strategies from a smartphone, tablet, or laptop - anytime, anywhere.

TDR Soil Moisture Sensors - Cutting-edge, digital, true time-domain reflectometer (TDR) soil moisture sensors accurately measure soil moisture, EC, and temperature.

Substrate Selection – The Precision Irrigation Controller can be configured to accurately measure and report using several types of growing substrates.

OTA Updates - Our controllers regularly receive over-the-air software updates that add new features and enhance existing ones over Wi-Fi.

Alerts - Stay informed on all active and historical alerts from your Growlink systems. Fanatical Support - Free support from a Growlink specialist (during office hours).


What’s In The Box                                                                                        

Precision Irrigation Controller

TDR (VWC, EC, Temperature) Sensor(s)

24 VAC Power Supply

Mounting Hardware


Controller and Sensor Dimensions                                                            


Quick Setup Guide                                                                                        

1. Download the Growlink app from the Apple App Store, or Google Play Store.


2. Open the Growlink app and tap Create Account.  


3. After creating an account, log into the app.

4. Tap on the settings icon in the top right corner and then tap Connect To Controller.

To view the video walkthrough of connecting a controller, click Here

If it is your first time creating an account, you will be automatically prompted to Setup A New Device.

5.  - Plug in your Growlink device to power it on.  

    - The LED should be blinking blue. If not, hold the SETUP button for 3 seconds

    - Make sure your mobile device is connected to the internet.

NOTE: The first time using the Growlink app you will be prompted to allow Bluetooth access. This is required to setup all Growlink controllers.


6. For Iphone users: Tap New Bluetooth Device, then tap on the controller you wish to connect to. A successful connection will be indicated with a "Congrats" message.

- If using a Legacy model controller (Non-Bluetooth), tap "Legacy Wi-Fi Device"

- From the "Waiting for Wi-Fi connection" screen, follow the instructions shown on your device to complete the Wi-Fi connection process

For Android users: The Growlink app will detect if your controller is a Bluetooth device or a Legacy model device. Simply tap on the controller you wish to connect to once it shows on the screen.


7. After the Bluetooth connection process is complete, a list of available Wi-Fi networks will appear. Tap on the network you wish To connect to, enter the network password, then tap Next.



8. Name your controller (i.e. Flower Room Irrigation).


9. After controller registration, tap on Go To Settings.

From the Controller Profile page, you can set where you are located, time zone, Day Start & Day End (Lights On and Lights Off). After making changes, tap Save and you will be returned to the Main Dashboard.


Controller and Sensor Placement                                                             


Note: The example shown is the recommended probe placement in a 6"x6"x6" rock wool cube.

Please visit this link to view probe placement in other commonly used substrates.


Module Wiring                                                                                             

Watch the video below for wiring instructions



Crop Steering With Irrigation                                                                       


Manage plant growth by adjusting environmental factors and/or irrigation to encourage a crop's desired outcome. Changing environmental conditions allows the influence of growth toward the desired growth stage, typically vegetative or generative.


To receive a complete guide to Crop Steering, visit this link  scroll to the bottom of the page and enter your e-mail to receive our free e-book.

Programming Sensor Triggers, Timers & Schedules                                  

HubSpot Video



Input/Probe readings not showing up on all inputs OR input ports were moved from original placement: If you are not seeing all 4 input readings showing up on the Dashboard or are seeing incorrect readings after moving input terminals, press the Reset button located on the front of the controller.



Controller didn't connect to Wi-Fi: If you are unsuccessful in the first attempt to connect your controller to your Wi-Fi network, hold down the Setup button located on the front of the controller for approximately 12-15 seconds until you see a rapid flashing blue light. Once you see the rapid flash, immediately release the Setup button. This will put the controller into Listening Mode (Blinking Blue), and you will then restart the connection process outlined in step 4 of this guide.


The Wi-Fi network being used has changed: In the event you need to re-connect the controller to an existing Wi-Fi network, put the controller back into Listening Mode (see above) and follow the Controller Connection process outlined in step 4.


Controller LED Status Light Color Codes

  During device setup and operation, these are the LED light indicators:

  • Solid White: Firmware Startup
  • Slow Flashing Green: Wi-Fi connecting
  • Fast Flashing Green: Wi-Fi waiting on IP address
  • Fast Flashing Cyan: Wi-Fi connected, connecting to cloud
  • Fast Breathing Green: Loading configuration and detecting probes
  • Slow Breathing Green: Connected to cloud and running
  • Slow Flashing Blue: Wi-Fi configuration mode
  • Safe Mode: Slow breathing magenta
  • Safe Mode Requested: Fast flashing magenta
  • Firmware Updating: Slow flashing magenta
  • Slow Flashing Blue: Wi-Fi setup mode