Swamp,
Very good point. I am an older fart so, I don't realize how cheap some tecno gadgets have become. Some degree of cleaning might be desirable, especially if the homeowners have allergy problems. Still as I posted to Bull, there is a lot of potential problems. ( The various duct types ). Your fear could be well justified. Take care and thanks for being here.
tom
" The most certain way to assure total victory is to understand that anything less, is a defeat."