This printer wouldn't load filament 🤔. I thought it might be filament broken off inside the extruder gears, but this was not the case. I took the hot end apart and found the filament was jammed or melted inside the tube that screws into the nozzle heater. It wouldn't get hot enough to loosen the filament, so I replaced the heat sink and the filament tube from the spare parts box. I then ran about 6 inches of cleaning filament through the nozzle and then did a test print with ASA. It worked just fine after that. 🤗
I'm thinking that it would be a good idea to run a bit of the cleaning filament through the nozzle whenever changing filament on all of the printers.