Electronic pellet burner controller – NPBC-V3C-2 / NPBC-V4C-2
W
AY
OF
O
PERATION
A burner controlled by NPBC-V3C-2 or NPBC-V4C-2 can work in continuous automatic mode or
in timer mode. While in timer mode, the burner works only during the intervals of the day and the
days of the week set by the user. While working, it goes through several stages: cleaning, igniting,
unfolding the fire, modulated burning process according to the current and set temperature of the
boiler, intermediate cleaning performed during the burning process, extinguishing and cleaning
again. The current stage of the burner is displayed in green color on the bottom line of the main
screen.
Every ignition begins with a cleaning cycle to clean all leftovers of the previous burning. At first
only the main fan works for as long as it is set in the menu
Factory Settings
→
Burning Setup
→
Fuel X
→
Cleaning, line Start
, column
Fan
. Then the Cleaning fan also starts and works for as
long as it is set in the same menu, line
Start
, column
FC
. The cleaning procedure is followed by the
igniting phase.
The ignition procedure starts with loading the first fuel dose in the burning chamber. The electrical
heater fires up the fuel while the fans provide the air flow. The procedure is performed in 3 stages.
During the first stage only the ignition heater works to reach the necessary temperature for ignition
faster. During the second and the third stages the ignition heater works along with the fans that
provide the necessary oxygen for the ignition and blow the heat from the heater to the fuel. It is
recommended to set lower speed for the fans during the second stage, so that they won't cool down
and blow off the flame and higher speed for the third stage to increase the air flow. To set the
maximum duration of each stage and the fans' speed go to the menu
Factory Settings
→
Burning
Setup
→
Fuel X
→
Ignition
. The controller measures the temperature of the exhaust gases before
the beginning of the ignition by using the pt100 temperature sensor. After the ignition it starts
increasing and the controller constantly monitors the difference between the current temperature
and the initial value. If the difference is higher than the parameter for ignition in the menu Factory
Settings → Flame Detection the controller detects that the ignition is successful. The ignition heater
turns off and the burner goes to Unfolding fire phase to stabilize the fire. If the pellets do not ignite
during the set time for this, the burner loads a new portion and makes a new attempt for ignition.
This happens only for the first 3 ignition retries and the pellet portion for each of them is
respectively 100%, 50% and 25% of the set dose. After the last attempt for ignition, the burner stops
and displays an error message for ignition fail. The parameters for the first dose and the ignition can
be set in the menu as many retries as set in the menu
Factory Settings
→
Burning Setup
→
Fuel
X
→
Ignition
. The parameters for detection of the burning fire can be set in the menu
Factory
Settings → Flame Detection.
The successful ignition is followed by the smooth unfolding procedures. If the burner goes instantly
to burning on 3rd power level, when the fire is still unstable and the burning chamber is cold, the
high air flow from the fan might blow off or smother the flame. To avoid this, the burner waits for
the first dose of pellets to burn out and then slowly increases the power to the highest required
power level according to the temperature difference between the set temperature and the current
temperature of the boiler, starting with the lowest level P1. The parameters for the Unfolding fire
process can be set from the menu
Factory Settings → Burning Setup → Fuel X → Unfolding
Fire
.
The next phase is the burning control. NPBC-V3C-2 and NPBC-V4C-2 have settings for 4 different
power levels. Three of them are used for the burner's normal work. The 4th power level maintains
the burning fire to avoid unnecessary cycles of extinguishing, cleaning and ignition when the water
in the boiler has reached the set temperature. Of course, if there is no need for more heat in the
User Manual / ver3.8
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