Rain dial irrigation system. Turn on manual and all I hear is clicking? Problem?

A clicking sound in a Rain Dial irrigation system when you turn it to manual mode can indicate a problem with the system. The following are a few common causes of this issue:

1. Solenoid valve problem: The solenoid valve may be faulty or not working properly, causing the clicking sound.
2. Low voltage: If the system is not receiving enough voltage, it can cause the solenoid valve to make a clicking sound when trying to open.
3. Dirty valve: Debris in the valve can cause it to stick, making a clicking sound when attempting to open.
4. Broken wiring: If the wiring to the valve is damaged or broken, it can cause the clicking sound.

In order to diagnose and solve the problem, it is recommended to check the solenoid valve, voltage, and wiring, and clean or replace parts as necessary. If you are not familiar with the system and its components, it is best to contact a professional irrigation technician for assistance.