Question
Greetings Jeff, When I restarted my sprinkler system after the winter, I
noticed that all of the irrigation solenoids click continuously (about once per
second) and they don't turn on.  First, I thought that they may be sticking
and/or crusted over from the winter months, and I flushed them manually (by
opening the small thumb screw), but no use.  The valves click for about a
minute and they quiet down without opening, then the controller moves on to
the next valve.  Can you help?

Answer
I can think of a couple of things that may be happening.  One is that your common wire (ususally the white wire) is not connected to the controller well, or it may have a short in it somewhere along the way.  Check all connections both at the controller and the valves.  Secondly, it could be that the controller is not putting out enough power to make the operate the solenoids properly.  If you have a multimeter or voltage meter that reads 24 volts, you can check the output of the controller by connecting the leads to the zone terminal on the controller (1 -?), and the other to the common terminal.  Turn on the corrosponding station manually.  The reading should be 24 volts AC.