Table of Contents
Advertisement
6
Maintenance
6.1
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
contents of this manual and in compliance with the
DANGER
standards and regulations of current laws.
6.2
Maintenance programme
6.2.1
Maintenance frequency
The gas combustion system should be checked at
least once a year by a representative of the
manufacturer or another specialised technician.
6.2.2
Safety test - with no gas supply
To perform commissioning in safety conditions, it is very
important to check correct wiring between gas valves and burner.
For this purpose, after checking that connections comply with the
burner wiring diagrams, it is necessary to carry out a start-up
cycle with gas cock closed (dry test).
1
The manual gas valve must be closed using the locking/
unlocking device ("Lock-out / tag out" procedure).
2
Ensure that burner limit electrical contacts are closed
3
Ensure that minimum gas pressure switch contact is closed
4
Try to start the burner
The start-up cycle must occur according to the following steps:
–
Fan motor start-up for pre-purging
–
Gas valve leak detection control, if applicable
–
Pre-purging completion
–
Achievement of the ignition point
–
Power supply of the ignition transformer
–
Supply of gas valves
As gas is closed, the burner cannot ignite and its control box will
switch to stop or safety lockout condition.
The actual supply of gas valves can be checked by inserting a
tester; some valves are equipped with lights (or closing/opening
position indicators) that activate as soon as they are powered.
IF
POWER
OCCURS IN UNEXPECTED MOMENTS, DO
NOT
OPEN
DISCONNECT
ATTENTION
WIRINGS, CORRECT THE ERRORS AND
CARRY OUT THE WHOLE TEST AGAIN.
20174375
SUPPLY
OF
GAS
VALVES
THE
MANUAL
VALVE,
POWER
SUPPLY,
CHECK
Maintenance
Before carrying out any maintenance, cleaning or checking
operations:
Disconnect the electrical supply from the burner
by means of the system main switch.
DANGER
Close the fuel shut-off valve.
DANGER
Wait for the components in contact with heat
sources to cool down completely.
6.2.3
Checking and cleaning
The operator must use the required equipment
during maintenance.
Combustion
Carry out an analysis of the combustion flue gases.
Significant
differences
measurements indicate the points where most care should be
exercised during maintenance.
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.
Flame sensor
Minimum current for correct working is 70 µA.
If the value is lower, it could be due to:
–
exhausted sensor;
–
low voltage (lower than 187 V);
–
bad regulation of the burner.
In order to measure the current, use a microammeter of 100 µA d.c.,
connected in series to the sensor, as in the scheme, with a capacitor
of 100 µF - 1V d.c. at the same level of the instrument (Fig. 36).
D1143
Burner
Clean the outside of the burner.
Fan
Check to make sure that no dust has accumulated inside the fan
or on its impellers, as this condition will cause a reduction in the
air flow rate and provoke polluting combustion.
32
GB
with
respect
to
the
previous
Fig. 36
Advertisement
Table of Contents
