09/07/2026
The slimy, brownish-yellowish gunk—commonly called “drain snot,” bacterial zoogloea, biofilm, is a frequent cause of clogs in high-efficiency furnace (and AC) condensate drain systems. When heavily located around a floor drain and left untreated it can cause drainage issues and clogs in your main line.
Friendly reminder to get your AC/Furnace serviced yearly!
-RSI