Introduction: Install a Hunter Solar Sync Sensor

About: Engineer that worked in space program and aerospace; enjoy tinkering.

The Solar Sync ET sensor is an advanced weather sensor that calculates evapotranspiration (ET) and adjusts Hunter controllers daily based on local weather conditions. Solar Sync measures sunlight and temperature, and uses ET to determine the correct seasonal adjustment percentage value to send to the controller. The controller then uses its programmed run time and adjusts to Solar Sync’s seasonal adjustment value to modify the actual irrigation run time for that day. In addition, the Solar Sync ET sensor integrates Hunter’s popular Rain-Clik™ and Freeze-Clik® sensors providing quick response in shutting down your irrigation system during rain and/or freezing conditions. The Solar Sync is compatible with most Hunter controllers. A great way to manage watering of your lawn.

Step 1: Step 1: Unplug the Controller for Safety

Unplug the power and make sure the controller is blank. Open up the second latched cover to expose the wiring inside the unit. Just to be safe, slide the black switch to the [Power Off] position.

Step 2: Install Sensor Unit

Find a location on the side of the house that gets sun throughout the day. The sensor needs to be oriented upright and the swivel bracket can be moved for mounting on angled surfaces. The optional gutter bracket can be used to install on a gutter. I installed it on the AC stand on the side of the house that gets the most sun. Shaded areas will impact the data collected by the Solar sensor. Once installed, start routing the sensor wire, using a staple gun to tack it up. Be careful to not pierce the wire when you staple.

Step 3: Route Wire Into Controller Box

Use a 9/64" drill bit to put a hole into the controller box. There are several plugs you can use on the right side and under the controller box to feed the wire into the unit. I carefully drilled a hole in the PVC pipe that went in from the bottom and snaked the wire into the unit. Be careful when you do this because the plastic sheathing on the wire can get nicked/scraped and the exposed wire will get cut or corrode in the weather.

Step 4: Connect the Sensor

Find the [SEN] terminal and unscrew the bridge jumper. This jumper is not needed, but I kept mine just in case. Connect the Green and Black wires to the sensor. You can trim the extra wire length. I kept the extra wire length and wrapped it neatly inside the case, this is optional.

Step 5: Plug in the Controller

Slide the switch back to [POWER ON]. Close the unit up again and plug in the controller. Set the [Rain Sensor] switch from Bypass to Active. It will show Sensor in the display window to show it is getting data. Let the unit collect data for a few days. I noticed that I was over watering my lawn during the summer by as much as 60%. This is money wasted. Good luck.