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Have a 20 year old system with 9 zones. Can't find the location of any of the control valves and two are not working.
Was told by a landscapper there is a controller out there that has a way to send a audiable signal to find the control valves. I spoken to the orginal installer, but he could not offer any exact location of the control vales. Tried to follow the underground piping and after poking a hole in the supply line (nice fountain) decided to quit.
Is there a controller that has built in technology to locate unknown location of control vales?
Any suggestions will help.

Thanks for the information on the locator device. I guess there is not a controllar that has built in technology to locate valves as I was told. Thanks, Wet_Boots