I still don’t understand how those cheap filament dryers work: they fully enclose the spool and heat up the air for a few hours. But where does the moist air go? It’s still trapped in there with the filament. It makes no sense!
I always leave the filament dryer a bit open so the warm air can escape, taking the moisture to a better place (far away from the filament)
That I am aware of. But without any circulation the hot air will simply cool down and condensate once I turn off the dryer, wouldn’t it? Leaving either highly saturated air or even some water droplets, ready to be absorbed by the filament again