I demonstrate a diagnostic algorithm for workup of a defective solenoid as a cause of failure to water a sprinkler zone in a home irrigation system. This algorithm would be a reasonable approach if you have a single zone of sprinklers that delivers inadequate water when activated by the controller, but which works fine when activated manually. This review covers some basics of Irritrol valves and a Hunter ProC controller, but the information is more broadly applicable to most home irrigation systems. If your system does not deliver water for one specific zone when you open the manual control bushing, search for the more recent video titled "troubleshooting irrigation sprinkler valves" on my channel, here    • Troubleshooting irrigation sprinkler ...  

During the repair I use the technique of "voltage drop testing", which is designed to find high dynamic resistance connections. Many such connections can be hard to find using traditional static methods. For a more general review of the structure of home irrigation systems, see my other video titled "how to fix a leaking sprinkler head".

These systems use a transformed 25 volt AC power system, but even with low voltage power there is a chance of dangerous or damaging misadventure. Also be wary of the risk of water damage to your home if your system fails to shut off or is accidentally left on. Whenever working with electrical power, be careful for the safety of yourself and your family. Be sure to read any manufacturers literature available regarding your system.

This video is published in good faith for entertainment purposes only, and it is not a comprehensive guide. I am not a professional electrician or irrigation consultant. Any misadventure resulting from your attempt to repair your sprinkler system is your responsibility.