At a setting of 6.5 (about 385 F) you should have excellent vapor output and brown leftovers. Getting vapor in the bag but having green leftovers doesn't make sense to me. They have had a problem with a certain number of units (a particular production run maybe?) getting a bad kink in the internal tubing and restricting the air flow, but I have no idea if that's your problem. The Volcano Classic has a 3 yr. warranty. Take advantage of it. You can contact them in the US or Germany.

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