MIKRO P7 - P12
22
EN
cod. 3540T988 - Rev. 01 - 01/2014
Burner lighting
•
Switch on the power, operating the main switch ahead of the burner.
•
To fill the auger with pellets, see sec. 3.4.
•
close the thermostat line (boiler/room).
Burner setting
1.
Connect a combustion analyser to the boiler outlet and leave the burner working at
max. for 30 minutes; meanwhile, check the efficiency of the flue pipe.
2.
MAKE SURE THE COMBUSTION CHAMBER IS IN NEGATIVE PRESSURE
3.
Check the combustion at max. burner power (adjusted according to boiler nominal
power).
4.
Combustion parameters:
•
O
2
between 5% and 9%
•
CO between 150 and 1000 ppm
To set the burner, change the fan set point by modifying the relevant parameter (see
the section “
Service parameters menu
” and
and table 2
in cap. 2.4).
The CO value depends on the quality of pellets, the amount of dirt in the combustion
head and boiler draught.
To operate the burner in MODULATING mode, it is necessary to modify the param-
eter “
T18
” and then carry out points 5 and 6 described below.
5.
Check the other burner steps, reducing the value of parameter u02 to 1 (see the sec-
tion “
Service parameters menu
” and
table 1
in cap. 2.4).
6.
Set the parameter u02 to the correct value.
4.3 Maintenance
Checks and controls
A
Periodically check the cleanness of the burner parts which will tend to get dirty
depending on the quality of the pellets or due to incorrect burner adjustment.
A
Periodically check the pellet hopper and remove dust from the bottom. An ex-
cessive amount of dust can affect the proper supply of fuel to the burner.
The burner requires periodical maintenance which must be performed by qualified per-
sonnel at least once a year.
The basic operations to carry out are:
•
check and cleaning of the internal parts of the burner and boiler as indicated in the
following sections;
•
complete combustion analysis (after at least 10 minutes' operation) and check of
correct settings;
Opening the casing and removing the burner
B
Before carrying out any checking or cleaning inside the burner, disconnect the
power to the burner by means of the main system switch.
To open
Undo the screws (A) and remove the casing (B). The internal components, motor, shut-
ter, etc., can be directly accessed.
To disassemble
Undo the screws (A) and remove the casing (B), undo the nut (C) and disconnect the
body, undo the fixing screws (D) and remove the nozzle (E).
fig. 10
Checks on parts and components
Fan
Make sure no dust has accumulated inside the fan and on the blades: it reduces the air
flow, thus causing pollutant combustion.
Combustion head
Make sure all parts of the combustion head are intact, not warped by the high tempera-
ture, free of impurities coming from the room, and correctly positioned.
Photoresistance
Remove any dust on the glass. The photoresistance is press-on; to remove, pull it out-
wards.
4.4 Troubleshooting
The burner is equipped with an advanced self-diagnosis system. In case of a burner
anomaly, the display (Detail 7 - fig. 1) flashes indicating the fault code.
There are faults that cause permanent shutdowns (marked with the letter
"A"
): to restore
operation press the button
"P"
(Detail 5 - fig. 1) for 1 second; if the burner fails to start,
it is necessary to firstly eliminate the fault.
Other faults cause temporary shutdowns (marked with the letter
"F"
) which are automat-
ically reset as soon as the value returns within the burner's normal working range.
Table. 3 - List of faults
E
D
C
B
A
Code Fault
Cause
Cure
A01
No ignition shutdown
Pellet container empty
Fill the container with pellets
Auger cable broken or disconnected Restore the connection
Faulty igniter resistance
Replace and empty the head
of pellets
Combustion head dirty
Empty and clean it
Pellet feed duct obstructed
Free it, make sure the combustion
head is not clogged and empty it if
necessary
F02
Parasite flame elimination
The demand for heat has ended,
but the burner detects flame
Wait for end of post-ventilation
A02
Shutdown for parasite flame
Photoresistance short circuit
Replace the photoresistance
Extraneous light strikes the
photoresistance
Eliminate light source
A04
Auger safety thermostat block
Incorrect ignition parameters
Check the transparent parameters
03=51 and 04=12
Boiler under pressure
Clean it and check correct minimum
flue draught (10Pa)
Faulty safety thermostat
Replace it
F05
Faulty pipe pressure adjustment
Pressure sensor connection tube
squashed
Replace
Fan motor damaged
Replace
Fan dirty
Clean it
F06
Pressure transducer fault
(disconnected)
Wiring disconnected
Check the wiring or replace
the sensor
F10
Boiler shell probe fault
(if enabled)
Sensor damaged
Check the wiring or replace
the sensor
Wiring shorted
Wiring disconnected
A03
Wiring fault
Jumper of terminals 13-14
not connected
Check the wiring
