I had a need for a tower starting at 220 deg. to check a heavily filled PLA filament at higher tempertures too. None of the towers made it all the way from 240 down to 160 or from 220 down to 180 degree. Extruders always jammed at some point when it became to hard to push the filament through.

A snapshopt of tempinjector.py from https://github.com/fablabnbg/tronxy-xy100/
is also included.