Sorry to necropost, but it sounds like your cold-end cooling is not working (that's what causes the filament to expand above the extruder and not be able to be retracted through the Bowden tube; Bowden setups need more robust cooling than direct drive). The original E3D Kraken came with a watercooling setup, and I assume that the Chinese knock-offs also have it? Air cooling is insufficient whenby CalebPetersenPhD - General