In our unit there are 3 access panels. One in the bathroom at the bottom of the tall storage cabinet and 2 in the kitchen area. In the kitchen there is one on each side of the furnace/fuse panels. I have included pictures below to show what I found when opening.
I opened them so I could figure out how to winterize the unit and what issues I might have to deal with regarding water pump, hot water heater, and bathroom drains.
Behind the panel nearest the sink was the water pump and I was pleasantly surprised to find a bypass line for antifreeze fill. You turn off the line coming from the water tank, uncap the antifreeze fill line and the water pump will push the antifreeze through your system. Nice.
Behind the panel below the fridge was the back of the hot water heater with 2 valves you also need to turn so water no longer gets into the tank. This will keep the antifreeze out of the hot water tank when you winterize. You just manually drain the tank from the outside and maybe blow it out with air.
The last panel has a drain, plus the lines ( for city water and black flush) coming in from the outside. One of the lines goes up in the wall and has some sort of black valve thing at the top where it splices back to another line. You can barely reach it through a hole on the shelf above. I wonder if that is the city water pressure switch to keep the pump from running when on city water?
I have to remember to mark the valves as to the ďnormalĒ position so I can properly reset them in the spring.
I hope this helps someone. We didnít address this stuff in our walkthrough so I had to do my own discovery. It was fun and interesting.