420GLS Rain Sensor Installation Guide

1. Locate the nearest roof location to the controller, making sure there are no overhanging trees or other obstructions. RainBrain™ needs clear access to rainfall to work effectively. If using a ladder, ensure it is stable before accessing the roofline. The best location for 420LS Rain/Freeze Sensor is under a roofline or gutter with the rain sensor fully exposed to the elements. (fig. 1)
2. Select the desired rain sensitivity. Sensitivity settings range from 1/8” to 3/4”. (fig. 2) The higher the setting, the longer RainBrain™ will remain inactive before shut-off. To adjust, turn the cap while lifting up and locking into the desired setting. No adjustment is needed for freeze protection on the 420LS.
3. Using the supplied attachment screws, fasten RainBrain™ to a solid fascia board or other solid mounting location using a screwdriver. Adjust the aluminum bracket so the plastic housing of the RainBrain™ is level and the top opening is pointed up. (fig. 3)
4. When using the 201E on donduit, remove the bracket and cut the wire ties. Place RainBrain™ inside a 3/4” slip fitting with silicon sealant. (fig. 4)
5. Tuck the extension wire behind the nearest trim or corner board and run the wire back to the controller. (fig. 5) If using a staple gun to secure the wire, be careful not to puncture any of the insulation. If additional wire is needed to reach the controller, an additional 50’ of 20 gauge wire can be added before heavier wire is needed. (Consult the factory for longer wire runs)
6. If the controller has a space on the terminal strip marked “Sensor”, simply connect the two wires of RainBrain™ to the sensor terminals. (fig. 6)
7. For controllers that require a “Normally Open” sensor cut the red wire from RainBrain™ where it meets the copper extension wire. Strip the unused blue wire (Normally Open) and attach it to the copper wire. Seal the connection with heat shrink tubing or electrical tape. Cut any bare wire from the end of the red wire.
8. If the controller has no sensor input, disconnect the common wire (usually white) from the terminal. Attach one wire of RainBrain™ to the common wire and secure with a wire nut or tape. (fig. 7) Attach the remaining wire on RainBrain™ to the common terminal You’re done!

Testing: Manually start the irrigation system with a dry RainBrain™. Depress the spindle located top/center of RainBrain™ with your finger. All sprinklers should stop within 30 seconds. Release the spindle and the sprinklers should resume normal operation.

Warranty: All RainBrain™ products are covered by a one (1) year warranty. If you have any problem with materials or workmanship of this sensor, we will repair or replace it free of charge. Weathermatic assumes no responsibility for installation costs. Replacement disks are available at a nominal charge at any time.

CAUTION: 420GLS is designed for low voltage use only. 420GLS is not intended for use with high voltage irrigation systems. Please consult factory for details.