Riello RS 160/M BLU, Instruction Manual

Page: 29 / 52

27 20168488 GB
Start-up, calibration and operation of the burner
6.3 Servomotor adjustment
The servomotor provides simultaneous adjustment of the air
damper, by means of the variable profile cam and the gas
butterfly valve. The servomotor rotates by 130° in 42 s.
6.4 Burner start-up
Feed electricity to the burner via the disconnecting switch on the
boiler panel.
Close the thermostats/pressure switches and turn the switch in
Fig. 29 to position “
MAN ”.
As soon as burner starts, check the fan rotation direction
through the flame inspection window.
6.5 Burner ignition
If the motor starts up, but the flame does not appear and the
control box goes into lockout, reset it and wait for a new ignition
attempt.
If ignition is still not achieved, it may be that gas is not reaching
the combustion head within the safety time period of 3 seconds.
In this case, increase gas ignition delivery.
The arrival of gas to the sleeve is indicated by the U-type
pressure gauge (Fig. 27 on page 26).
Once ignition has taken place, proceed with burner global
calibration operations.
6.5.1 Burner adjustment
The optimum adjustment of the burner requires an analysis of
flue gases at the boiler outlet.
Adjust in sequence:
1
Ignition output
2 Maximum output
3 Minimum output
4 Intermediate outputs between the two
5 Air pressure switch
6 Maximum gas pressure switch
7 Minimum gas pressure switch
6.5.2 Ignition output
According to EN 676.
Burners with MAX output up to 120 kW
Ignition can occur at the maximum operation output level.
Example:
•
max. operation output: 120 kW
• max. ignition output: 120 kW
Burners with MAX output above 120 kW
Ignition must occur at a lower output than the max. operation
output.
If ignition output does not exceed 120 kW, no calculations are
required.
If ignition output exceeds 120 kW, the regulatory standard
sets that the value be defined according to the control box
safety time "ts":
for "ts" = 3s, ignition output must be equal to or lower than 1/3
of max. operation output.
Example
MAX operation output of 600 kW.
Ignition output must be equal to or lower than:
•
300 kW with ts = 2 s.
• 200 kW with ts = 3 s.
ATTENTION
Do not alter the factory setting for the 5 cams;
just check that they are as specified below:
Cam I:
130° . Limits rotation toward maximum
position. When the burner is at MAX output,
the gas butterfly valve must be fully opened:
90°.
Cam II:
0° . Limits rotation toward minimum position.
When the burner is shut down, the air
damper and gas butterfly valve must be
closed: 0°.
Cam III:
30° . Adjusts the ignition position and the
MIN output.
Cams IV and V: Not used.
Fig. 28
D3923
DANGER
Check that the lamps or testers connected to the
solenoid valves, or the pilot lights on the solenoid
valves, indicate that no voltage is present. If they
indicate the presence of voltage, stop the burner
immediately and check the electric connections.
Fig. 29
1 2
D791