Burner Calibration - Riello RL 70 Manuel D'entretien

FAN AIR GATE VALVE ADJUSTMENT
D699
(A)
Burner
Off
On
(C)
RL 70 RL 70
MDO MGO
GPH N° GPH
5 2,0 6
6 2,3 7
7 2,6 8
8 2,7 9
9 2,8 10
11
12
13
RL 70 RL 70
MDO MGO
kg/h mbar kg/h
40 8,5 40
50 8,6 45
60 8,8 50
70 9,2 55
60
70
Stage
1 2
1st STAGE
N° = Notch 2)(A)
N°
1.5
1.7
1.9
2.1
2.3
2.5
2.7
3.0
2nd STAGE
mbar = air pressure in 1) with zeropressure in 2)
mbar
7.2
7.4
(1)
With shutter 4)(C)p.6 retracted
7.7
8.0
8.2
8.3
(B)
1°
2°
D469
(D)
(E)
D700
11

BURNER CALIBRATION

FIRING
Set switch 1)(C) to "ON".
During the first firing, during the passage from
the 1st to the 2nd stage, there is a momentary
lowering of the fuel pressure caused by the filling
of the 2nd stage nozzle tubing. This lowering of
the fuel pressure can cause the burner to lock-
out and can sometimes give rise to pulsations.
Once the following adjustments have been
made, the firing of the burner must generate a
noise similar to the noise generated during oper-
ation. If one or more pulsations or a delay in firing
in respect to the opening of the light oil solenoid
valve occur, see the suggestions provided on p.
15: causes 34 to 42.
OPERATION
The optimum calibration of the burner requires
an analysis of the flue gases at the boiler outlet
and interventions on the following points:
• 1st and 2nd nozzles
See the information listed on page 5.
• Combustion head
The adjustment of the combustion head al-
ready carried out need not be altered unless
the 2nd stage delivery of the burner is
changed.
• Pump pressure
12 bar: this is the pressure calibrated in the fac-
tory which is usually sufficient for most purpos-
es. Sometimes, this pressure must be adjusted
to:
10 bar in order to reduce fuel delivery. This ad-
justment is possible only if the surrounding
temperature remains above 0°C. Never cali-
brate to pressures below 10 bar, at which pres-
sures the cylinders may have difficulty in
opening;
14 bar order to increase fuel delivery or to en-
sure firings even at temperatures of less than
0°C.
In order to adjust pump pressure, use the rele-
vant screw 5)(A)p.10.
• 1st stage fan air gate valve
Keep the burner operating at 1st stage by set-
ting the switch 2)(C) to the 1st stage position.
Opening of the air gate valve 6)(B) must be ad-
justed in proportion to the selected nozzle: the
index 1)(A) must be aligned with the notch
2)(A) specified in table (D). This adjustment is
achieved by turning the hex element 2)(B):
- in rh direction (- sign) the opening is reduced
- in lh direction (+ sign) the opening increases.
Example RL 70 - 1st stage nozzle 6.0 GPH:
2,3(A) notch aligned with index 1)(A).
When the adjustment is terminated lock the
hex element 2)(B) with the ring nut 1).
• 2nd stage fan air gate valve
Set switch 2)(C) to the 2nd stage position and
adjust the air gate valve 6)(B) by turning the
hex element 4)(B), after having loosened the
ring nut 3)(B).
Air pressure at attachment 1)(E) must be ap-
proximately the same as the pressure specified
in table (E) plus the combustion chamber pres-
sure measured at attachment 2). Refer to the
example in the adjacent figure.
NOTE: in order to facilitate adjustment of hex el-
ements 2) and 4)(B), use a 3 mm Allen key 5)(B).