I have a 40 watt epilog mini that is hooked up to a do-it-yourself fume extractor. After replacing the activated carbon there is no odor for about 8 hours of machine operation then the odor becomes increasingly detectable. So why isn't it lasting longer? I've heard other people say the same amount of charcoal lasts them an entire year.
So the system is: machine-pipe-wooden filter box (prefilter, prefilter, 12" empty space, 5" tray (12"wide 24" long 5" deep) of loose activated carbon) pipe at bottom of box- blower - pipe then goes outside of building.
It's the same story for:
General Carbon C40 bituminous coal 4mm pellets
Virgin Coconut Shell
Thank you for any ideas or advice