How to Program the Holman Two Dial Low Pressure Tap Timer (CO1603)

By Grover Koelpin 1 comment

Installing and programming your
Essential 1603 Low Pressure Series Tap Timer can be done with these easy steps.
Start by installing the battery. Remove battery cover and battery tray. Insert two Triple A alkaline batteries and then replace the battery cover. To program the
Essential Series 1603 Low Pressure timer start by turning the left dial to select
the watering frequency. You can select from every hour up to every seven days.
Turn the right dial to select the watering run time. Watering run times can
be set from one to 120 minutes. To confirm the selected program,
Press and hold the ENTER button for three seconds. The LED light will go
solid and then flash off. The watering program will only start after the
selected frequency has been entered. The enter button can also be used to delay the first start time. Each press of the enter button will add one extra hour and watering will then start at the selected frequency. The Essential 1603 tap timer
also comes with manual watering options. For non-stop watering set the left
frequency dial to RESET and set the right dial’s run time to ON. The tap timer
will run until you decide to turn it off. For an auto stop manual watering option,
set the left frequency dial to reset and set the right dial’s run time to the
desired duration. The tap timer will run on this time selected and automatically
stop. After manual watering, you must set the program again. For more
information on the Essential 1603 Low Pressure Tap Timer visit our website at

1 Comment

Daniel West

Dec 12, 2019, 6:25 am Reply

Found my new rainwater drip feed controller for the raised beds. Literally exactly what I have been looking for. Cheers

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