thanks. but it's a hot air duct...

"buffalobill" wrote in message
...
On Jan 3, 1:41 am, "John91" wrote:
It's about my 40-yr old 2-storey house in midwest Canada. After taking
off
part of basement ceiling, I found something weird with a heating duct. It
runs up from basement to main floor along an exterior wall (built into
the
fiberglass insulation), and maybe further up to the second floor, and to
attic??? I'm sure no heating vent in the house uses this duct. I just
can't
figure out where is goes. It sends hot air to attic to do heating?
possible
for an old house?

please help solve the mystery. Thanks.

cold air return. fresh air supply for combustion. laundry chute. wire
chase. radon vent. ?