What’s the best way to winterize a controller for the long and cold Minnesota winter? Should I leave it plugged in or should I remove the battery and unplug it? I don’t care about retaining the program information and I was wondering which way was better to help prolong the life of the controller.
I live in sunny Southern California but I believe I read once that you should go ahead and unplug the controller. Take out the back up battery. I believe the controller will last longer this way. Like you said, you don't care if you lose the programming.
It was suggested to me that it would be better to keep a current running though the controller during the winter months to keep condensation from forming inside the controller. I would think if condensation were a problem that it would be stated in the controller’s manual to leave it plugged in to avoid the condensation.
For Outdoor mounted controller leave the power on and the dial / switch in the "Off" position. The heat from the transformer will keep the enclosure warm enough to keep condensation from forming inside the controller enclosure. The dial in the "OFF" will keep the controller from activating the solenoids in the field.
For Indoor mounted controller You may either leave the power on and the dial/switch in the "Off" position or you may remove the battery backup and unplug the transformer.
I think the better idea would be to relocate the timer/controller to an indoor location. Having it inside would prolong it's life alone. Are you able to move it into a garage or basement?