A drip tray gets the thankless task of guiding air conditioning condensation in the coil to the exterior of your home. A continuous supply of water allows algae and fungus to form on the surface of the pan, creating a thick coat of slime. Over the years, the slime will build inside and shake the drain line guiding the condensation. Taking away the slime in the tray is essential to the health of the air conditioning system. After removing the slime, a couple of simple measures will ensure it doesn’t return.
Turn off the power to the air conditioning system.
Lift up the coil access door and pull it away in the unit to gain access to the coil and drip tray. If your accessibility panel has screws, then remove them with a 5/16-inch nut runner or Phillips screwdriver prior to lifting the panel.
Put on chemical-resistant gloves. Spray an aerosol alkaline coil cleaner over the coils as well as the surface of the drip tray. Allow the cleaner to sit on the surfaces, per the manufacturer’s directions. This will remove any fungus or algae on the coil, causing it to fall into the drip tray and loosen the drip tray slime.
Scrape the slime in the drip tray with a metal putty knife. Discard the stuff in a disposable container. Spray additional cleaner in the tray to loosen any remaining slime. Clean the tray thoroughly with a brush. Wipe the inside of the tray with a rag to remove any remaining slime.
Hold the end of a garden hose in the drip tray drain. Have an assistant turn on the garden hose to flush the slime out of the condensate drain. Turn off the hose and place it apart.
Place two condensate cleaner tablets from the drip tray. Install the access panel and turn on the power to the air conditioning system.