So the system I am going to be working on is all Rain Bird valves (8 zones) & panel, with short (< 3 ft.) underground run from house to manifold box. It was winterized and during the process one of the zones was noticed to be leaking, so the valve had to be manually opened and some debris was found and cleaned out - while I was at it I checked out all the valves for debris, and reinstalled them. Nothing electrical was messed with. As is my normal procedure, the master shutoff was closed in the house, but the panel was left on normal schedule so the valves would open and close for a few weeks and clear any residual water before the fall freeze. The owner turned off the control box sometime in December / January, but left it plugged in as usual. Anyway, now during spring pre-activation inspection, it was discovered that three of the eight zone valves are humming / hot, and the transformer at the control box is really hot. Confirmed the control panel was set to off. Unplugged the control panel and humming stopped (obviously no surprise there). I don't suspect any damage to the underground control wires. I though OFF meant no current to valves. I'm guessing that's not right. #1 what's the best way to deal with this? Should I just tell them, opps, I overtightened the valves and they've been trying to close all winter so your motors and transformers have been slowly frying, or what? Is it likely realistically that this could be from some other problem? #2, do you advise your customers to unplug the control box over the winter? Thanks in advance for all help and information!