and connects to this rubber tubing:
Not a big deal, as I figured it could be fixed with some epoxy. So I unscrewed it from the trim piece, and happened to look inside, and found a small sensor fully covered in dust. It reminded me of the MAF sensors in the engine bay. I'm guessing this one helps the HVAC unit read the ambient temperature so as to be more accurate in its output, whether hot or cold.
I instinctively blew off the dust - this thing I've circled in red was fully covered in dust before I realized this might be an interesting blog post and took this photo:
|I took the photo only AFTER I blew away most of the dust! It was fully covered!!
I wonder how many R33 owners out there have stumbled upon this? In any case I'm hoping this results in a more responsive HVAC unit, especially this summer!
EDIT: Thanks to Chris Brox for sending me his picture of a REALLY dirty one!