An nozzle of my Snapmaker U1 failed with printing and the clog ended up breaking the frail temperature sensor.
The spare about are expected to arrive within about a month (stock runners out, and I didn't had spare parts of these because they have never broken on my old printer).
I moved the nozzle heater and sensor from head 2 (E1) to head 1,since the left head is like a master and you can't do without apparently. I set the min_temp of [extruder1] in the printer.cfg file super low. And now it can boot up again.
The printer runs just fine on the other nozzles now, just can not do a nozzle offset calibration and such since that requires heating the nozzles. Meaning nozzle 1 has a wrong offset (but can be used on its own), nozzle 2 is completely out, and nozzle 3 and 4 can be used for multi material printing.
It's current printing! So no time to waste. Let us engineer and print more, and enjoy the hobby
I think it needs a bit of airflow. Unless your trying to make plasma