Ac tune up. Replaced 20x25 air filter in ceiling return vent, customer no longer uses merv filter. Cleared trap and drain line, water is being removed outside. Took temperature readings and had a 20 degree split which is very good. Tested blower motor, tested normal. Outdoor capacitor was just replaced and tested normal. Contactor was in good shape. Compressor and outdoor fan amp readings were both in range. Found a significant amount of bacterial growth all along indoor coil in air handler. Recommended installing a UV light to kill and attack future bacterial growth from building up.