Bingo

"The Daring Dufas" wrote in message
...
The UV light around the evaporator coil kills the
the micro-critters that can grow on the wet coil.
That area of any HVAC system is where microbes can
grow because that's where a lot of water and debris
can collect. Some evaporator coils are coated at the
factory with an antimicrobial compound that will help
kill off the little beasties. Anything that can kill
mold and mildew around the evaporator will also keep
the odor level down. I've seen yeast grow in the darn
things, some folks like to bake their own bread.

TDD