Willie The Wimp wrote:
Natural gas is principally methane. Per "Combustion" at:

http://en.wikipedia.org/wiki/Methane

the methane combines with sufficient oxygen, producing carbon dioxide
(CO2), water, and heat.

Carbon monoxide (CO), a poison, is produced as a by-product but, given
sufficient oxygen, is almost instantaneously converted to harmless
CO2.

If sufficient oxygen is not present, a certain amount of CO can be
produced.

I have a garden-variety 3-yr-old updraft 80% furnace. It has 3
burners.
As near as I can tell, the heat-exchanger consists of 1 unit with 3
tubular chambers which wind around and around, finally exhausting
to a standard roof-vent.

Following is just a theoretical question:
If I could "wire" my furnace such that everything save the inducer
motor worked fine, given sufficient oxygen, ventilation, etc, should
I expect
my CO-detector to issue a warning?

Would appreciate responses from those who fully understand the process
of methane oxidation or have non-sensationalized personal experience:
anyone can read the warnings.

I would think any CO would go up the chimney, unless the heat exchanger is shot.