Unigas RG91 Manual Of Installation - Use - Maintenance page 16

PART II: INSTALLATION
Priming the pump and adjustments
1 remove the electric panel cover;
2 prime the oil pump, by means of the related contactor: check the motor rotation and keep pressed for some seconds until the oil cir-
cuit is charged bleed the air from the M pressure gauge port of the pump (see picture below), loosening the cap without removing
it; then release the contactor;
3 Remove the actuator cover.
4 Turn the burner on by means of its main switch A (Fig. 10): if the burner locks (LED B on in the control panel) press the RESET
button (C) on the control panel (Fig. 10) - page 19;
5 start the burner up by means of the thermostat series and wait until the pre-purge time comes to an end;
6 Keep the burner to the low flame stage by disconnecting the TAB thermostat (remove the bricge between terminals 6 and 7).
7 Proceed as follows acting on the ST1 actuator cam to adjust the air flow rate in the low flame stage, checking the combustion
values:
8
I
II
III
PG60: Berger STA4.5
Refer to the next table for cams functions.
"Air adjustment in high flame" cam
Air adjustment in low flame - Stand-by - Ignition cam
Auxiliary cam for the opening consent to the second fuel valve
Berger STA4: this actuator is not provided with the manual control of the air damper. The adjustment of the cams is carried out by
means of a screwdriver, by twisting the VS screw located inside the cam.
Berger STA6: this actuator is not provided with the manual control of the air damper. The adjustment of the cams is carried out by
means of the cam lever
Siemens SQN72: a key is provided to move cams I and IV, the other cams can be moved by means of screws. On the Siemens

actuator the AUTO/MAN mode is provided (see picture).
9 by removing the bridge between the 6 and 7 terminals of the TAB thermostat , the actuator moves to the position (degrees) set for
the ST1 cam (low flame cam);
10 to decrease the low flame position (and then decrease the opening angle of the actuator), move the cam to a lower position: the
actuator will close to the new position of ST1;
11 to increase the low flame position, move the cam higher to the required position, make the bridge between the 6 and 7 terminals
only for a while and then remove it immediately: the actuator will move for just few degrees towards the high flame, then it will move
down to the new ST1 low flame position;
12 now, charge the oil ciruit of the second nozzle by pressing the P1 button (see next picture);
Suntec J6-J7
VR
ST1
ST2
MV
PG70 - PG81: Berger STA6
16
M
III
II
I
PG60 - PG70 - PG81: Siemens SQN72
BERGER STA4.5 BERGER STA4.5
I
II
III
AUTO/MAN
Siemens SQN72
III
ST2
I
ST1
II
MV