I have a control system that is mounted outdoors on a wall in a standard metal power center -- just like hundreds of other control systems (Jandy Aqualink, Pentair EasyTouch, and Goldline.) But, for some reason, this one is getting water inside the power center and the water always damages the same spot on the board. You can see a hard water trace on the back of the board where it runs down.
So how does the water get in to a sealed power center that is made to be mounted outdoors? Well, first I thought that it must be coming in past the weather stripping on the door. I replaced that. Next, when that didn't work, I tapped up the gap between the top of the box and the removable front service panel, but the water still came in.
Finally, I think I found a clue:
My solution? I decided to allow the water an alternative outlet besides where it connects to the board. To do this, I stripped some of the covering off (to allow it to escape) and then bent the wire into a U shape and poked it down into a hole that exits the control panel at the bottom. This way, the water should drip outside the power center.