I mainly print PLA on the SV07 Plus. This means that is what’s inside the print head after a print job finishes. I always unload the filament after, so I can store it as dry as possible.
Here is the tip: to load TPU, I preheat for TPU, but then I insert a short piece of PLA and load that. Once the old filament starts flowing out of the nozzle, I take out the PLA piece and load the TPU.
Works nicely.
If I try to load TPU directly, it is unable to push out the old filament.
It’s a good idea to use actual cleaning filament whenever changing filament types. Residue in the nozzle can contaminate the new filament and/or may restrict the nozzle diameter due to different extrusion temperatures.
Heat the nozzle to the last printed temperature +5°. Load cleaning filament until visibly purged. Then do a cold pull.
On the subject of cold pull, many seem to feel pulling while the filament cools will be adequate but filament in an extruder heats and cools by contact with the nozzle – from the outside in. I’ve found it better to allow the nozzle to cool well below the glass transition temp and then gently pull while approaching the glass transition during re-heating rather than during the cooling. To my mind, this ensures the residue is softened first while the cleaning filament still has a strong bond to the contaminates.
Just my 2¢