Combustion Head Setting; Electrodes Adjustment; Pump Pressure And Air Output - Riello GRG4S Manuel D'entretien

4.3 COMBUSTION HEAD SETTING,

It depends on the output of the burner and is carried out by rotating clockwise or counterclockwise the setting
screw (6) until the set-point marked on the regulating rod (7) is level with the outside plane of the nozzle-holder
assembly (1).
In the sketch the combustion head is set for an output of 3.50 GPH at 12 bar.
The set-point 2.5 of the regulating rod (7) is at the same level with the outside plane of the nozzle-holder as-
sembly (1) as shown in the schedule.
4.4 ELECTRODES ADJUSTMENTS,
ATTENTION
L e a n t h e d if f u s e r d i s c - h o l d e r
assembly (1) on the nozzle-holder
(2) and lock it by screw (3). For
prospective adjustments loosen
s c r e w ( 4 ) a n d m o v e t h e e l e c -
trodes assembly (5).
To have access to the electrodes
carry out operation as described in
chapter 4.2 ( page 6) "R ECO M-
MENDED NOZZLES".

4.5 PUMP PRESSURE AND AIR OUTPUT

The burner, in order to guarantee good smooth
starts, irrespective of the type of boiler, is fitted
with a hydraulic device which, independently of
the control-box, reduces the fuel- and air-flow.
At ignition, the pressure at the nozzle is 9 bar.
After 3 - 9 seconds, it automatically increases to
12 bar.
The air-flow, initially adjusted to the low setting, is,
at the change-over of pressure, automatically
brought to the air-flow required for the big flame.
SETTING FOR THE LOW IGNITION-FLAME
(See fig. 14)
ADJUSTMENT OF AIR SHUTTER
Unloosen the screw (8), by approximately one full
turn; in this way, the burner remains permanently
on low flame.
Unloosen the nut (5), turn the screw (4) until the in-
dicator (6) reaches the position desired.
Then lock the nut (5) and tighten the screw (8).
ADJUSTMENT START DELAYING DEVICE
This is set at 9 bar at the factory.
The pressure gauge must be mounted in place of
plug (4, fig. 8, page 4).
Should it be necessary to re-set or alter such pres-
sure, this can be done, by adjusting screw (7), al-
ways after having loosened screw (8).
1916
(see fig. 12, page 6)
(see fig. 13)
WARNING
4.5
Fig. 13
Fig. 14
S7161
7
GB
MEASURES MUST BE
RESPECTED
0
6
– 0.5 mm
4
5
3 2 1
–
7
mm
D5085