A heating and cooling system which includes in combination a blower, a hot
air furnace and an air conditioner unit with interconnected ducting and a
filter/purification member positioned on the upstream side of the blower.
The filter/purification member functions to mechanically filter solids
with the purification component functioning to act as a catalyst for UVPCO
when exposed to ultraviolet light. The filter is a mechanical filter which
further contains a titania component and a source of UV light adjacent the
filter to facilitate UVPCO.