that is a wiped film, not a falling film.
that won’t work…you need to suck WAAAAY harder to distill cannabinoids.
(it is appropriate of a falling film, but you don’t have one of those)
which tells you you need to turn the heat up (but don’t bother until you can pull 100um or better on your empty still). if nothing is evaporating, nothing will condense.
start here: Boiling Point of THC