▲ 3 r/Mold
My parents' HVAC guy said this was dirt, but I am not convinced
They are hesitant on getting a second opinion and content on avoiding the hassle, but I worry this is not good for them, former smokers with sleep apnea in their mid-to-late 60s. The square vent is on the ceiling above their bed.
u/andie_pantz — 18 hours ago