Use caution when firing with the combustion
air control wide open. Only burn cord wood
in this manner. Small dry pieces of softwood
and construction scraps will burn very intensely
using this method and may damage the firebox.
Medium Combustion
This is the recommended mode of operating
the BIS
®
Ultima CF fireplace and should be
the one normally used since it will deposit the
least amount of creosote on the glass and in
the chimney. The combustion air control must
be 3/4 closed (
Figure 1
) and pushed in to close
the air boost. The precise setting will depend
on many factors, including chimney length and
the moisture content of the wood.
For instance, a long chimney will necessitate
closing the damper more. To obtain the proper
combustion, close the damper completely, then
open it about 1/4” to 1/2”. Three medium size
pieces of wood should be burning on a bed of
hot coals. The heat output will be approximately
30,000 BTU per hour and the loading time will
be about every 3-4 hours. Softwoods may be
burned using this method but the time will be
substantially reduced.
Slow Combustion
When the air combustion control is completely
closed, the fireplace is in a slow combustion
phase. If the hearth is hot enough, slow combus-
tion will not extinguish the fire, but there will be
a noticeable change in the flame pattern. The
flames will be slow and may appear dirty if the
wood is too wet (moisture content of 20% and
more). Do not allow the wood to burn without
flame, since this will produce excessive creosote
in the unit.
Creosote may accumulate on the glass door. This
method of burning should be used only after
operating the BIS Ultima CF fireplace with the
air control opened
(
Figure 1
)
to produce a hot
fire for about an hour or at medium pace for at
least three (3) hours. Slow combustion can be
used at night in order to reduce the heat output
and to prolong the burn. The loading time will
be between 6-8 hours.
REFUELING FOR BEST PERFORMANCE
The BIS Ultima CF fireplace will operate best if
attention is given to operating the unit with the
damper fully opened
(
figure 1
)
after refueling
in order to bring the firebox and the chimney
system up to their optimum operating tempera-
ture. Combustion efficiency is relative to firebox
temperature. A temperature of 932º F (500º C)
and up, with a visible flame, in the upper part
of the firebox indicates a maximum efficiency.
To obtain this temperature, the fireplace must
be operated with the primary air and air boost
controls fully opened during 10 to 20 minutes
after reloading, depending on the heat and on
the moisture content of the wood.
Once you have reached the desired temperature,
the air boost can be closed and the primary air
set to a medium setting. You know you have
reached the desired temperature when, closing
the primary air control, you can see a flame
at the top of the firebox. The benefit of this
technique will be cleaner glass, less creosoting,
greater efficiency and the most pleasing fire for
your enjoyment. If your fireplace is equipped
with a forced air system, make sure the central
blower is turned off during reloading to avoid
smoking problems.
SMOKING –
CAUSES AND TROUBLESHOOTING
To reduce the likelihood of smoking when open-
ing the door, set the combustion air controls to
the left before opening the door. Your fireplace
has been designed and tested to provide smoke
free operation. Occasionally, there may be a
small amount of smoking upon lighting the fire,
until the chimney heats up but this should not
continue. If the fireplace continues to smoke
it is probably for one of the following reasons:
A. Negative pressure in the house -
As the fire burns, air goes up the chimney.
This air must be replaced through leakage
into the house or through the outside air duct.
When operating the BIS Ultima CF fireplace,
open a nearby window temporarily to check
if there is adequate replacement air supply.
B. Blowers operating (e.g.: range hood) -
These blowers draw air out of the house
and may actually cause a negative pressure
in the house. Turn off all blowers and open
a nearby window to determine if this is the
cause of the problem.
C. Wet wood -
Wet or tarred wood will smoulder
and smoke instead of burning properly. Your
dealer can help you determine if you have
properly seasoned wood for burning.
D. Dirty or blocked chimney -
Check to make
sure the chimney is clear and clean. If dirty
call a certified chimney sweep or use a
properly sized chimney brush to clean.
E. Chimney not long enough -
The minimum
chimney height is twelve (12) feet (3.7 m) not
including the fireplace height. The chimney
must extend at least three (3) feet (915 mm)
above its point of contact with the roof and
at least two (2) feet (610 mm) higher than
any roof or wall within ten (10) feet (3 m) of
it. When installed with offsets, the minimum
chimney height is fifteen (15) feet. Additional
height will increase draft and will decrease
the tendency to smoke.
F. Poor chimney draft -
With no fire, there should
be sufficient draft to exhaust cigarette smoke
introduced under the baffle. Chimneys installed
against an outside wall without protection may
generate back draft problems which will cause
start-up problems. To prevent this, open a
nearby window, roll up a piece of paper and
light it. Then, hold it in the upper part of the
firebox to warm up the chimney. Wait until
the draft is sufficient, then start the fire.
G. Blower for forced air kit operating -
Make
sure that the blower is in the “off” position
when you open the fireplace door for reloading.
IMPORTANT CAUTIONS
A. Do not block the hot air vents to the fireplace
as this will cause the fireplace to overheat.
B. Never use gasoline, gasoline-type lantern
fuel, kerosene, charcoal lighter fluid, or
similar liquids to start or ‘freshen up’ a fire
in this fireplace. Keep all such liquids well
away from the fireplace while it is in use.
C. Do not burn coal. The sulphur in coal will
corrode the firebox and chimney.
D. Do not burn driftwood which has been in the
ocean or salt water. The salt will corrode
the firebox and chimney.
E. Do not burn wood in the area in front of the
grate.
F. Do not abuse the unit by burning paper, or
cardboard or construction material such as
pressed wood, plywood or lumber. Wood
protectors, metallic paper, coal, plastic,
waste, sulphur and/or oil will damage the
fireplace.
G. Do not allow the wood to smoulder or burn
without flame, since this will produce
excessive creosote in the unit as well as
increased particulate emissions.
5
