What can I pour down my AC drain to unclog it?

To keep your air conditioning condensate drain line clear and prevent future clogs caused by algae, mold, and bacterial slime, you can pour a mixture of warm water and distilled white vinegar down the T-pipe vent opening once a month. Vinegar is mildly acidic and acts as a safe, natural cleaning agent that kills organic buildup without damaging the PVC pipes or corroding internal metal components. Alternatively, you can use specialized, manufacturer-approved enzymatic pan tablets or algaecide tablets designed specifically for HVAC condensate pans, which slowly dissolve over time with each condensation cycle to keep the drain line completely free-flowing. You should completely avoid using harsh chemical drain cleaners like lye or sulfuric acid, as these toxic products generate intense heat, can melt plastic PVC fittings, and pose severe safety hazards to your skin and eyes if they splash back during application.