4
Understanding Operating Modes
LOW Mode (If Enabled)
NOTE: LOW mode should only be enabled if there
is a problem with the electric ignitor. Contact your
dealer to enable LOW mode. LOW mode should
be disabled once the problem has been solved.
LOW mode is used to maintain the re when the heat
demand is low or not present.
NOTE: For most applications, the LOW heat
output and air settings should be set to the
lowest setting when using wood pellets. The
LOW heat output and air settings may require
additional adjustment if the re does not relight
when shifting from LOW to MEDIUM, or if the
outdoor furnace overheats when changing to a
lower mode.
• The LOW heat output setting should be set as low
as possible while still enabling the re to relight
when shifting into MEDIUM mode.
• If there is no fuel left in the burn chamber and the
re has gone out, the heat output is set too low.
Increase the LOW heat output setting.
• If the water temperature increases above 195˚F
(90˚C) when the furnace is in LOW, the heat
output is set too high. Decrease the LOW heat
output setting.
Monitor the outdoor furnace operation to determine if
additional changes are needed, keeping in mind that
it may take several cycles of the heat load before this
becomes apparent.
IGNITION Mode
Upon entering ignition mode, the augers will start for
several seconds to add enough fuel to the burner. The
fan will then speed up to the ignition fan speed and the
ignitor will heat up. If the ignition sequence exceeds
ten minutes, the augers will start a second time to add
more fuel to the burner. The controller will attempt this
ignition sequence three times.
Corn Only - Ignition Ramp Up Mode
When the combustion controller is set to corn mode,
there is an additional function that slowly raises the
feed rate until it reaches the actual MEDIUM feed rate.
The lower feed rate will be in effect until the burner
temperature is above 850˚F (454˚C) for at least three
minutest. The MEDIUM Mode LEDs will be ashing
during this time.
MEDIUM Mode
In general, the MEDIUM heat output setting should
be set high enough to minimize the amount of time the
controller is in HIGH mode. Increasing the MEDIUM
to HIGH differential will also keep the combustion
controller from shifting to HIGH mode.
The outdoor furnace is most efcient when it is operating
in MEDIUM mode and not shifting often into HIGH
mode. The combustion controller changes to MEDIUM
mode when the water temperature drops 10˚ below the
water temperature setpoint. MEDIUM mode represents
20%-60% of the outdoor furnace’s heat output capacity.
NOTE: For most applications, the default MEDIUM
heat output setting is adequate to allow the
outdoor furnace to operate efciently. For some
heat load requirements or when burning a fuel
other than wood pellets, it may be necessary to
change this setting.
• If the outdoor furnace operates in HIGH mode
much of the time, increase the MEDIUM heat
output setting one step. If the outdoor furnace
changes from MEDIUM to LOW mode when
there is a heat demand, lower the MEDIUM heat
output setting one step.
• In a higher heat load installation such as radiant
oor heat, an abrupt heat load change (i.e., when
there is no longer a call for heat) will cause the
combustion controller to shift quickly from HIGH
to MEDIUM to LOW mode. A fuel such as wood
pellets that burns easily will continue to provide
heat in LOW mode and can cause the water
temperature to increase above 195˚F (90˚C). In
this instance, decrease the MEDIUM heat output
setting so there is less remaining fuel when the
controller changes from HIGH to LOW mode.
• Upon entering MEDIUM mode, the combustion
controller will turn the fan on in its highest setting
for a few seconds to clear the burner. It will then
slow down to its medium speed. If the burner
temperature is high enough, the controller will
stay in medium and cycle the augers at the medium
feed rate.
• If the burner temperature is too low, the ignition
sequence will start.
