What does the ET Window Start and the ET Window Length settings do?
The Weather Reach Receiver must be programmed to the time of day your sprinkler controller is set to water and how long it takes to complete the watering of all the zones. For example, your controller may be set to start watering at 2:00 am and will continue to water each zone until 5:00 am. This sprinkler cycle takes 3 hours to complete. In this example the ET Window Start of your Weather Reach Receiver would be set to 2:00 and the ET Window Length is 3 hours. The ET Start Window is not used to start a watering cycle but is used to allow the Weather Reach Receiver to control watering during that period.