Controller for pellet oven – NPBC-V3C-B
W
AY
OF
O
PERATION
A burner controlled by NPBC-V3C-B 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
. When the photo sensor detects the light from the burning fire, 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 3
rd
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-1 has settings for 4 different power levels. Three of
them are used for the burner's normal work. The 4
th
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 heating installation for longer period
of time, the burner turns off. The portion of pellets for each power level is a function of the auger
motor's capacity and activate time and the cycle between two of its turnings on. The parameters for
each power level's settings are auger motor's active time, cycle between two turnings on and main and
exhaust fans' speed. These parameters can be set in the menus
Factory Settings → Burning Setup →
User Manual / ver 3.7
http://www.naturela-bg.com/en/
page 6 of 30
