Your problem is your dust collector system. If you have fine dust in the
air while the furnace is running, it will draw the dust in with the
combustion air from your shop. The dust goes in with the air into the
burner tubes where it mixes with the gas. The gas/air mixture then
goes up through the burner plate or orifices, but the dust will be left
behind as it settles out of the air stream, eventually plugging the
burners. If the fires are off (shut the furnace down), there is no
air flow and no dust gets transported in and deposited.

HOWEVER, the dust-laden air that plugs your furnace also plugs your
lungs and you are setting yourself up for serious health problems in
the future if you don't eliminate the flour-like dust from the air. It
will get into your lungs as you breathe in and stay there, causing
polyps, cancer, asthma or any number of other respiratory ailments
(anyone for emphysema?).

A well-designed cyclone dust collection system with proper 0.3 micron
filtration after the blower will eliminate the dust problem. If you
have a 10" table saw, you need a cyclone dust collector that provides
a "real-world" 900-1000 CFM, at least, and don't use the cloth filter
bags. You need pleated, high-efficiency filters.

Bill Pentz nearly died from the effects of wood dust aggravating a
pre-existing condition. He has done extensive research on the subject
and has designed a cyclone dust collector. I produce a kit based
on his research and design work by his invitation. I also produce a
matching welded steel blower housing to match. Add a motor, impeller,
filters, and ductwork and you have a first-class cyclone dust collection
system for less than the price of a new Kirby, Rainbow, or Interstate
Engineering household vacuum cleaner. Not only will you get rid of the
furnace problem, but you'll be protecting your health at the same time.

For more info, see Bill's site at:

http://cnets.net/~eclectic/woodworki...lone/index.cfm

and the kit and blower-housing information at:

http://cnets.net/~eclectic/woodworki...larkesKits.cfm

Contact me privately if you have further questions.

Clarke

Larry Levinson wrote:

am in desperate need for advice about my basement woodshop and the
furnace/central air unit. we share the same space, with no separation.
the local utility guy just told me on the phone that my options are as
follows, or I will kill the unit ...

1) Turn off the unit while working (freeze the family.) at the end of
the session, open the front, vacuum it out and the area immediately
around it before turning it back on.

2) Box in the unit and figure out someway to supply air.

a) new outside air supply? sounds expensive.
b) louvered opening in the ``wall'' that backs on to the
laundry room? (lint issues, but obviously much less than sawdust.)
c) cut the access door, with louvers, in the laundry room
wall, which would elimate the workspace used by SWMBO for her jewelry
hobby.

what do all you guys do about this?

REALLY want to avoid having to move to the garage ...

UPDATE: I currently have a Jet 650 CFM dust collector with two
diverters to handle tablesaw, router, jointer and planer, plus an air
cleaner that I built from the American Woodworker plans a few years
ago.

UPDATE 2: anyone in the Trenton area want to go in on an
office/warehouse lease with me? there is a place on Flock Rd. Have yet
to ask the rent ...

TIA
Larry Levinson
Talking up to the vocal ...
LLevinson*Bloomberg.net
(remove the star etc ....)