Pacific Energy Pacific VISTA Installation And Operating Instructions Manual - page 11
070509-16
VISTA and CLASSIC-C
11
5055.3
CREOSOTE FORMATION AND NEED FOR REMOVAL
CHIMNEY FIRES
Theresultofexcessivecreosotebuildupisachimneyfire.
Chimneyfiresaredangerous.Chimneyinsidetemperatures
can exceed 2000° 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
likelyduringachimneyfire.Properclearancesarecritical
duringsuchafire.
Chimneyfiresareeasytodetect;theyusuallyinvolveoneor
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 inlet on stove.
3. Calllocalfiredepartment.Haveafireextinguisherhandy.
Contactyourlocalmunicipalorprovincialfireauthorityfor
furtherinformationonhowtohandleachimneyfire.Itis
most important that you have a clearly understood plan
onhowtohandleachimneyfire.
4. Afterthechimneyfireisout,thechimneymustbecleaned
and checked for stress and cracks before starting another
fire.Alsocheckcombustiblesaroundthechimneyandthe
roof.
AVOIDING A CHIMNEY FIRE
Therearetwowaystoavoidchimneyfires:
1. Do not let creosote build up to a point where a big chimney
fireispossible.
2. Donothavefiresintheheaterthatmayignitechimney
fires.Thesearehotfires,suchaswhenburninghousehold
trash, cardboard, Christmas tree limbs, or even ordinary
fuel wood; (e.g.. with a full load on a hot bed of coals and
with the air inlet excessively open.)
W
hen wood is burned slowly, it produces tar and other or-
ganic vapours, which combine with expelled moisture to form
creosote. The creosote vapours condense in the relatively
coolchimneyflueofaslowburningfire.Asaresult,creosote
residueaccumulatesonthefluelining.Whenignited,this
creosotemakesanextremelyhotfire.Thechimneyconnec-
tor 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
beremovedtoreducetheriskofachimneyfire.
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 burn-
ing requires small fuel loads, two or three logs at a time
or 1/4 to 1/2 of fuel load and leaving the air inlet relatively
wide open, especially during the first 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 the wood smoke is
passing, the more creosote will be condensed. Wet or
greenwoodcontributessignificantlytocreosoteformation
astheexcessmoisturethatisboiledoffcoolsthefire,mak-
ingitdifficultforthetarsandgasestoignite,thuscreating
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
combustionairwillhelptominimizethebuildup.