I got a call today for a zone that was only working half the time, to never. Sounded kinda odd. Turned it on at the controller, came right on. Hmmm. Metered the miliamps, perfect range. Hmm... Found valve, weathermatic nitro, 5 years old. Didnt think the diaphragm was out, but there wasnt a wire nut on the zone wire to the solenoid. Wire nut on, and noticed when I touched the wires the solenoid came on and off. All it was was a bad connection on one wire. He was expecting a 200$ valve repair job, turned out to be a 15 minute wire nut fix. Good thing, cause I was dead tired at the end of the day. Just had to share my joy.