David L. Martel wrote:
a,

Don't beat up on Tom because you don't use the proper terminology, use
the proper terminology.
You have a cold air return. It brings cold air from the house's interior
to the heat exchanger. The heated air then goes to your house. This air flow
is driven by a fan. There's usually a filter.at the entrannce to the cold
air return.
The heat exchanger sits inside a combustion chamber. This is where the
fire is. Hot gases are exhausted up to a chimney.
Now you seem to indicate that your chimney pipe ( a metal pipe) runs
through the cold air return prior to exhausting to the outside and you would
like to attach some vanes to the chimney pipe. Is this right?

Dave M.



This is my setup:
http://oee.nrcan.gc.ca/publications/...il_fig01_e.GIF

The heat exchanger, I suppose *is* on the hot side - but the flue *does*
pass through the cold air return in order to impart more heat to the
incoming air.

a