The combustion air control should be in the
closed position when the fireplace is not in use.
This will minimize air leakage up the chimney.
The combustion air control and the CAT bypass
damper control must be opened before opening
the door to minimize the possibility of back
draft coming into the room.
Accelerated Combustion
The maximum heat output for the WRT3920WS
fireplace is achieved by burning with the door
closed and the combustion air opened. By this
method, the WRT3920WS fireplace can produce
the maximum BTU of heat per hour. However,
it will be necessary to reload with wood every
one or two hours. This is the least efficient
method of burning the WRT3920WS fireplace.
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 WRT3920WS 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. 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” (6.4mm to 13mm).
Two medium size pieces of wood should be
burning on a bed of hot coals. The heat output
will be approximately 25,000 BTU per hour and
the loading time will be about every 3-4 hours.
Softwoods may be burned using this method
but the burn 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 combustion will
not extinguish the fire, but there will be a notice-
able 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 WRT3920WS fireplace with
the air control opened 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.
Figure 2 - Accelerated Combustion
Figure 3 - Medium Combustion
Figure 4
-
Slow Combustion
Figure 5 - CAT Bypass
Open
Closed
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
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