While getting an estimate for a new furnace the salesman rec a Second Wind Air Purifier which has a germicidal lamp and an ozone generator to remove smells in the air. Does this thing work or was he generating the wind? I will have two furnaces installed and he said I only need one of these things.

Sometimes it is nice to have every doohicky that the exclusive few have. What did he mean that you have a smelly, germy home? If the germs enter the ductwork because you make germy, smelly pollution, why do you want to eliminate them? Is there something you can do in the house to prevent germy, smelly products from entering the ducts? - maybe a filter and UV light at the entry to the ductwork, so the return duct doesn't transfer these products. Why does a heating system have to do the job? He wasn't very polite.