Originally Posted by WiYeti
I’ve poured iso alcohol down the line which would “fix” it for a few hours before it started up again.


I am no expert by any means, but I started thinking about this, then you mentioned this quote which made me more suspicious. How cold has it been? Condensation can form in the airline and freeze, iso alcohol is usually the cure. Could be ice building up in the airline. I could be way off here, but was just my first thought.

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