Excellent explanation, very didactic, especially placing the bimetallic in ice water to test if it opens or closes, a very similar process that is done with thermostats.
A humble suggestion, the images are too small, I assume that by adjusting the quality they have remained that way, reading your post on my mobile device I had to zoom in a lot to understand them, everything else is great.
RE: To do? The freezer of my refrigerator is full of frost and does not cool the refrigerator