Can you put drano in a clogged AC drain line?

No, you should never pour Drano or any other commercial lye-based chemical drain opener down your air conditioning condensate drain line under any circumstances. Commercial chemical drain cleaners are specifically formulated to dissolve organic hair and grease clogs in standard kitchen and bathroom plumbing traps, but they are completely unsafe and inappropriate for HVAC condensate systems. These harsh chemical products generate intense exothermic heat during their chemical reaction, which can easily melt, warp, or crack standard PVC condensate pipes and delicate plastic drain pans. Furthermore, if the clog does not clear immediately, the caustic chemicals will sit inside the lines and release toxic fumes that can be sucked into your ductwork and circulated throughout your entire living space, creating serious health hazards. Instead of Drano, use safe alternatives like white vinegar, hydrogen peroxide, or a wet-dry vacuum to clear the line.