@pierre286
I think Dremel 3D20 and 3D40 printers are similar.
So @STS might provide the solution for your extruder sensor Printer.cfg for Dremel 3D40
It looks like the sensor is connected to an ADS1118 https://www.ti.com/lit/ds/symlink/ads1118.pdf?ts=1732524720011&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FADS1118%253FkeyMatch%253DADS1118%2526tisearch%253Duniversal_search%2526usecase%253DGPN-ALT on the original printerboard. It’s probably a K-type thermocouple sensor.
You could try to install Klipper on the original printer board.
Good luck, hcet14