The 0.3 ohm coil is recommended for 30-80 Watts, probably DL. Now, 27 watts seems suspicious to me. If you don’t pull the air through it fast enough, it can cause gunking on the coil. The question is whether you use it in DL or MTL mode. This phenomenon can probably occur in MTL. Plus, the colored/sweetened liquids, plus the skill of little Chinese Chen is also a factor, as learned colleagues before me have written.
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