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7
Maintenance
7.1
Notes on safety for the maintenance
The periodic maintenance is essential for the good operation,
safety, yield and duration of the burner.
It allows you to reduce consumption and polluting emissions and
to keep the product in a reliable state over time.
The maintenance interventions and the calibration
of the burner must only be carried out by qualified,
authorised personnel, in accordance with the con-
tents of this manual and in compliance with the
DANGER
standards and regulations of current laws.
7.2
Maintenance programme
7.2.1
Maintenance frequency
The gas combustion system should be checked at
least once a year by a representative of the man-
ufacturer or another specialised technician.
7.2.2
Safety test - with gas ball valve closed
It is fundamental to ensure the correct execution of the electrical
connections between the gas solenoid valves and the burner to
perform safely the commissioning.
For this purpose, after checking that the connections have been
carried out in accordance with the burner's electrical diagrams,
an ignition cycle with closed gas ball valve -dry test- must be per-
formed.
1
The manual ball gas valve must be closed
2
The electrical contacts of the burner limit switch need to be
closed
3
Ensures closed the contact of the low gas pressure switch
4
Make a trial for burner ignition
The start-up cycle must be as follows:
–
Starting the fan for pre-ventilation
–
Performing the gas valve seal control, if provided
–
Completion of pre-ventilation
–
Arrival of the ignition point
–
Power supply of the ignition transformer
–
Electrical Supply of solenoid gas valves
Since the manual gas ball valve is closed, the burner will not light
up and its control box will go to a safety lockout condition.
The actual electrical supply of the solenoid gas valves can be ver-
ified by inserting a tester. Some valves are equipped with light
signals (or close/open position indicator) that turn on at the same
time as their power supply.
IF THE ELECTRICAL SUPPLY OF THE GAS
VALVES OCCURS AT UNEXPECTED TIMES,
DO NOT OPEN MANUAL GAS BALL VALVE,
WARNING
SWITCH OFF POWER LINE; CHECK THE
WIRES; CORRECT THE ERRORS AND RE-
PEAT THE COMPLETE TEST.
Maintenance
Before carrying out any maintenance, cleaning or checking oper-
ations:
Disconnect the electrical supply from the burner
by means of the main system switch.
DANGER
Close the fuel interception tap.
DANGER
Wait for the components in contact with heat
sources to cool down completely.
7.2.3
Checking and cleaning
The operator must use the required equipment
during maintenance.
Combustion
Carry out an analysis of the combustion discharge gases.
Significant differences with respect to the previous check indicate
the points where more care should be exercised during mainte-
nance.
Combustion head
Open the burner and make sure that all components of the
combustion head are in good condition, not deformed by the
high temperatures, free of impurities from the surroundings
and correctly positioned.
Voltage on the QRI flame sensor
Minimum value for correct operation: 3.5 Vdc (value on AZL dis-
play at about 50%).
If the value is lower, it could be due to:
–
sensor not positioned correctly
–
low voltage (lower than 187 V)
–
bad regulation of the burner
In order to measure, use a voltmeter with a 10 Vdc scale connect-
ed as in the diagram (Fig. 40).
D9174
35
GB
LMV...
X10-02 / 6
X10-02 / 4
X10-02 / 2
+
0...10 V
Ri > 10 M
Fig. 40
20061317
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