I have talked this one to death and edited papers about it.
What papers, please?
Basically when it is boiling at 1 atm, it saturates the bottom sensor, then the middle, leaving only the top one to show differences in power. Not that complicated. Other people made similar calorimeters and confirmed they work as described.
Sorry but that means nothing to me. I've been around the block a few times with several types of calorimeters and never saw that. What does "saturate" mean in this context? What do you mean by "top sensor"? The diagram shows two thermistors embedded in the wall, towards the top of the device, one offset a few cm radially from the first. What does that arrangement measure and why?