Pacific energy SUMMIT WOOD INSERT DESIGN-A, Nstallation And Operating Instructions

12 

SUMINSERTA    260407-20

Chimney Fires

The result of excessive creosote buildup is a chimney fi re. 
Chimney fi res are dangerous.  Chimney inside temperatures 
can exceed 2000 degrees F.  This causes much higher than 
normal temperatures in the chimney and on its exterior 
surfaces thus ignition of nearby or touching combustible 
material is more likely during a chimney fi re.  Proper clear-
ances are critical during such a fi re.

Chimney fi res are easy to detect; they usually involve one 
or more of the following:
 

- Flames and sparks shooting out of the top of the 
chimney

- A roaring sound

- Vibration of the chimney

In Case of a Chimney Fire

1.  Prepare to evacuate to ensure everyone’s safety.  Have 

a well understood plan of action for evacuation.  Have 
a place outside where everyone is to meet.

2.  Close air inlets on stove.

3. Call local fi re department.  Have a fi re  extinguisher 

handy.  Contact your local fi re authority for further in-
formation on how to handle a chimney fi re.  It is most 
important that you have a clearly understood plan on 
how to handle a chimney fi re.

4.  After the chimney fi re is out, the chimney must be 

cleaned and checked for stress and cracking before 
starting another fi re.  Also check combustibles around 
chimney and the roof.

- The services of a competent or certifi ed installer, (certifi ed 
by the Wood Energy Technical Training program (WETT) 
- in Canada, Hearth Education Foundation (HEARTH) - in 
U.S.A.,) are strongly recommended.

Avoiding a Chimney Fire

There are two ways to avoid chimney fi res:
1.  Do not let creosote build up to a point where a big 

chimney fi re is possible.

2.  Do not have fi res in the heater that may ignite chim-

ney fi res.  These are hot fi res, such as when burning 
household trash, cardboard, Christmas tree limbs, or 
even ordinary fuel wood; (eg. with a full load on a hot 
bed of coals and with the air inlet wide open).

Creosote

Formation and Need for Removal

When wood is burned slowly, it produces tar and other 
organic vapours, which combine with expelled moisture 
to form creosote.  The creosote vapours condense in the 
relatively cool chimney fl ue of a slow burning fi re.  As a 
result, creosote residue accumulates on the fl ue  lining.  
When ignited, this creosote makes an extremely hot fi re.  
The chimney connector and chimney should be inspected 
at least once every two months during the heating season 
to determine if a creosote buildup has occurred.  If creosote 
has accumulated, it should be removed to reduce the risk 
of a chimney fi re.

1.  Highest smoke densities occur when a large amount of 

wood is added to a bed of hot coals and the air inlet is 
closed. The heated wood generates smoke, but without 
ample air, the smoke cannot burn.  Smoke-free, clean 
burning requires small fuel loads, two or three logs at a 
time or 1/4 to 1/2 of a fuel load and leaving the air inlet 
relatively wide open, especially during the fi rst 10 to 30 
minutes after each loading, when most of the smoke 
generating reactions are occurring.  After 30 minutes or 
so, the air inlet can be turned down substantially without 
excessive smoke generation. Wood coals create very 
little creosote-producing smoke.

2.  The cooler the surface over which wood smoke is 

passing, the more creosote will be condensed.  Wet or 
green wood contributes signifi cantly to creosote forma-
tion as the excess moisture that is boiled off cools the 
fi re, making it diffi cult for the tars and gasses to ignite, 
thus creating dense smoke and poor combustion.  This 
moisture-laden smoke cools the chimney, compounding 
the problem by offering the smoke the ideal place to 
condense.

In summary, a certain amount of creosote is inevitable 
and must be lived with.  Regular inspection and cleaning 
is the solution.  The use of dry, seasoned wood and ample 
combustion air will help to minimize the buildup.