I'm trying to figure out what this component is, circled in orange.
It's part of an evaporative humidifier (Canopy) and points through a plastic window to the water in the base. I'm guessing it's an optical component of some kind, but I've not seen one quite like it before, and it's labelled as an IC, which is throwing me off.
It appears to consist of two semi-circular disks connected together behind a window.
The large metal legs beside it dip into the water and I presume are used to detect if there is water present by measuring the resistance, so another sensor would seem redundant.
These are the components on the other side of the board, if it helps: