I didn’t speak of any noise.
You are going through contortions to different bridge between a timer and a thermostat. Well, the difference is clear. It all has to do with the beholder. An I watching Melachah going on by itself or a Keili that’s left on.
Soaking dyes over Shabbos can also be a factory in operation. However, it isn’t noticed. It’s missing the Avsha Milsa aspect.