I’m thinking that your unit got overheated by steam coming from the bath. Did you cover the bath?
See the vents at the back of the top of the housing? Steam can enter there and play havoc with the electronics. I noticed that a couple of times when I was using something similar to cling wrap to cover the bath. (I eventually got a hole saw and cut an opening in the container lid for the PC to sit in) Now it can’t be affected by the steam at all (in fact, my Cambro container’s pretty much sealed now, so there’s next to no evaporation at all!) 
(see pic below)
(see pic below)