Not exactly sure what to make of it, but checking out the pictures of the different models on the PC website I found that the gray/black electric valve switches and the gray/black flush valves are labeled differently on four different units. I wonder if these valves are actually in different locations or just mislabeled? I am sure that on my unit the black electric valve is on top and the gray on the bottom, but I'm not sure about my flush valves.
- Mike