25
Problem: Rapid accumulation of creosote in furnace and flue.
• Use of high resin wood, such as
pine.
• Completely avoid using if at all possible. If hardwoods are not
available, fuel the furnace with smaller loads.
Possible Causes:
Remedies:
• Under-firing the furnace has
caused low flue gas temperature.
• Install flue gas thermometer and maintain stack temperatures
between 300° and 400° F.
• See #13.
• Insufficient chimney draft.
8 .
• Improper connection in stove
pipe causing air leakage or a
structural defect in the chimney
itself.
• Inspect entire flue run, from the exhaust stack of the furnace to the
termination cap. Repair as necessary.
• Fire box not receiving adequate
amount of oxygen.
• Chimney is not tall enough, see “10/2 Rule” on page 4.
• DANGER: Never use uninsulated stove pipe as chimney.
Uninsulated pipe cannot be used as an outside flue because it
causes rapid cooling of the stack gases, which causes them to
condense as creosote on the inside of the flue.
• Using uninsulated stove pipe for
the chimney.
Problem: Insufficient air flow from the heat registers.
• Return air not connected to
furnace from the house.
• Connect air to the home to circulate air flow.
Possible Causes:
Remedies:
• Excessive duct run to the house.
• Reduce duct run by placing the furnace closer to the house.
• Replace air filter.
• Air filter is dirty, restricting air flow.
9.
• The hot air supply is being short
cycled back through the return
instead of going down stream to
the house.
• Redirect the hot air supply to send it down the air duct supply line.
You may install a back draft damper from the direction of the return
air.
• If using flex duct, it is not straight
and pulled tight. A sagging line
will cause swirling in the duct and
reduct air flow.
• Ensure the flex duct is pulled tight and straight with no snags.
Always go into your main supply lines at a slant pointing down
stream.
• Remove 90° elbows and replace with 45° elbows.
• The use of 90° elbows in the duct
run.
