VALLEY COMFORT SYSTEMS INC.
1290 COMMERCIAL WAY, PENTICTON, B.C. V2A 3H5 -- PHONE: (250) 493-7444
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9
CALL THE FIRE DEPARTMENT
DO NOT REMOVE THE FLUE PIPES UNTIL THE FIRE IS COMPLETELY EXTINGUISED
CREOSOTE
Creosote can be a problem with any type of wood burning equipment, so it is important to know what it is and how to
avoid it.
Creosote is an oily or tarry liquid resulting from the distillation of wood during the process of combustion. It is present in
the gases given off all types of burning wood, and in its solid and semi-liquid state is highly combustible.
When creosote forms on the inside of flue pipes and chimneys it can build up considerable thickness. As the creosote
builds up, the draft opening is reduced. When the build up is permitted to take place over an extended period of time,
sufficient creosote may be present in the stack to cause a serious fire if ignited. All users of automatic wood burning
equipment should be thoroughly familiar with the causes, control and cure of creosote. When these are well understood,
automatic wood burning equipment, properly installed and used, will give less creosote build-up and reduce the fire
hazard.
CAUSES OF CREOSOTE FORMATION
Creosote condenses from the flue gases when the stack temperature drops below 250 degrees F (120 degrees C). The
amount of creosote deposited in the pipe and the chimney is affected by the amount of moisture in the flue gases, the
temperature of the stack, the amount of draft in the stack, and how completely the combustion elements in the flue gases
have been consumed in the process of combustion.
REMOVAL OF CREOSOTE
A:) When the flue pipe and chimney become coated because of operation under improper conditions, the only practical
way of cleaning is to disassemble the pipe and clean it and the chimney by scraping.
The best way to remove creosote from the chimney is with a two cone-shaped wire brush slightly larger than the
chimney. As they are pulled up the chimney, they scrape away the creosote.
B:) The small amounts of creosote that are normally deposited can be kept from accumulating.
1. Open the draft by turning up the thermostat if necessary for 20 or 30 minutes before adding fuel. This will
increase the stack temperature and cause any creosote in the pipe to dry. In the process of drying, the creosote
shrinks, and the scale falls from the inner wall of the pipe.
2. Remember a fast fire a day will keep creosote away. A small intense fire is preferable to a large smoldering one.
CONTROL OF CREOSOTE
A) Moisture in the flue gas can be kept low.
1. Use the driest wood obtainable.
2. Mix small pieces with every charge. These smaller pieces should be placed on the charcoal bed first, when
adding fuel.
3. Never use only large wood during mild weather when combustion is relatively slow. Add small pieces.
4. Always use dry, split wood in mild weather.
5. Never add more than a 12 hour supply at a time.
B) The temperature of the stack can be increased to reduce creosote formation.
1. Insulate smoke pipe extension so that it will be cooled as little
as possible before reaching the chimney.
2. Use an insulated chimney
C) The amount of draft in the stack can be controlled.
1. Have as few bends as possible
2. Insure adequate height and diameter
3. Prevent any air leaks
4. Eliminate any external obstructions at the chimney outlet.
D) The rate at which the wood is burned is dependent upon the season of the year and your heating requirements.
