Filament doesnt come out while printing, but little bits come out while its heating.
When it’s heated, can you depress the load button and push filament through? If not, the hot end is clogged somehow. Without knowing how, you should have a spare hotend in the box, and they’re easy to swap. They are considered semi-disposible if you can’t figure how to clean it, and you can get more from the snapmaker store.
If you can push filament through, the nozzle isn’t clogged. If you remove the filament, and look at the end, is part of the filament ground out? Filament should have some teeth marks from the brass gear, but the diameter should always be 1.75mm (or slightly greater where the teeth marks are).
Setting the print head too low can cause the print head to be so close to the print bed that it can’t push plastic out. The brass gears will grind the filament instead, leaving a hollow on the filament where there should be teeth marks.
I find that my print bed loosens up every ~6 months or so and starts causing calibration problems. Usually a poor first layer finish as the bed is slightly closer than expected. If I don’t catch it in time, it can lead to no extrusion, or even the print head digging into the bed.
During the filament change when its 220* it will push filament out, but during a print it wont push any out. I dont think this is a hot end issue but maybe I calibrated it too low. I will definitely try to calibrate it higher.
If you have access to the console, you can tell the extruder to extrude manually.
Follow the steps in 3d Print Guide_Walk Through > FINETUNE YOUR SYSTEMSETTINGS > EXTRUDER CALIBRATION. We’re just trying to extrude though, so you don’t need to measure anything or do the calculations (unless you want to - I didn’t need to on my original).
When the print head is in open air, the G1 E100 F100 command should extrude some filament. If that doesn’t happen, there’s something inside the print head preventing the extrusion. Listen for various noises that might give you an indication. I have heard of people that had minor grinding problems getting enough filament dust in the gear that the teeth can’t catch anymore. They dissembled the head and brushed the dust out of the gear.