41
March 2011
Flex Fuel Owner’s Manual
Now you can completely fill the firebox right to the
top with bulk material for a full burn, or a part load,
depending on demand for heat.
11: Bulk Materials Mode
FLEX FUEL
V 10.060 Tu, 12.09.10
Bulk materials
Boiler temperature:
Flue gas temperature:
Air factor:
Bulk materials!
XXXºF
13:44
XXXºF
X.XX
11.4 Smoldering Gas Extraction and Adding Fuel
More fuel may be added by activating the smoldering gas extraction function when the operational
status of the furnace is “Bulk materials”.
First ensure there is sufficient demand for more heat.
Activating Smoldering Gas Extraction
Smoldering gas extraction is activated by pressing the control knob on the start screen
(3 - 4 seconds). A short activation message appears. "Smoldering gas extraction! SAF reference run!“ is
then displayed on the status line.
The Secondary Air Flap (SAF) is now closed, the induced draft fan runs at maximum speed and the
primary air feed is interrupted. The text “Smoldering gas extraction! Please add more!” will appear on the
status line after several seconds!
Carefully
open the firebox door and start the filling process.
Deactivating Smoldering Gas Extraction
After filling is completed, close the fuel door and deactivate smoldering gas extraction by
pressing the ESC button for 3 - 4 seconds. A deactivation message briefly appears and the furnace
switches back to regulated operation.
Smoldering gas extraction is automatically deactivated after
several minutes.
11.5 Combustion Completed
Furnace combustion is completed when:
• the flue gas temperature drops below the factory default flue gas switch-off temperature and;
• the air factor is above 2.50 for a longer period of time (10 - 20 minutes).
The message “Stop system!” appears on the status line.
Note: The furnace may reignite if conditions permit.
Then close the firebox door and deactivate Smolder-
ing Gas Extraction. It is easiest to detect that firing
has been successful by monitoring the air factor. After
closing the firebox door this should quickly drop to
less than 2.00.