PART III: OPERATION
29
Fig. 3 - Burner front panel
Keys
B1
Lock-out LED
B2
Hi-flame operation LED
B3
Lo-flame operation LED
B4
“Ignition transformer operation” LED
B5
“Fan motor overload tripped” LED
G1
“EV2 opening” LED
G2
“EV1 opening” LED
G3
“Gas pressure switch signal ” LED
S1
Main switch
S3
Operation selector MAN - AUTO (operation in manual or automatic mode):
MIN = operation with minimum output
MAX = operation at the maximum output
A1
Burner Modulator (only on fully modulating burners)
A2
AZL..
Fuel selection:
In order to start the burner with natural gas or LPG, the operator must commute the selector on the burner control panel on (1) =
natural gas, or (2) = LPG.
If the selector is set on (1) the natural gas cock must be open, while the LPG cock must be closed. Viceversa if the selector is set
on (2).
Gas operation
Check that the control box is not in the lockout position; in case unlock it by pressing the relevant key (for further information on the
LMV.., see the related manual).
Check that the pressure switches/thermostats series enables the burner operation.
Check that the gas pressure is sufficient (signalled by an error code on the AZL.. display).
Burners fitted with gas proving system:
the gas proving system test begins; when the test is performed the proving system LED
turns on. At the end of the test, the burner staring cycle begins: in case of leakage in a valve, the gas proving system stops the bur-
ner and the lamp
B1
turns on.
At the beginning of the start-up cycle, the actuator drives the air damper to the maximum opening position, then the fan motor
starts up: the pre-purge phase begins. During the pre-purge phase, the air damper complete opening is signalled by the light
B2
on
(see front panel).
At the end of the pre-purge, the air damper is driven to the ignition position, the ignition transformer is energised (signalled by the
light
B4
on the front panel) then, few seconds later, the EV1 and EV2 gas valves are energised (light G1 and G2 on the front
panel).
Few seconds after the gas valves opening, the ignition transformer is de-energised and light
B4
turns to off.
The burner operates in the low flame stage; few seconds later the two-stages operation begins and the burner output increases or
decreases, driven by the external thermostats (progressive burners) or by the modulator (fully-modulating burners).
S1
B1
B2
B3
B4
B5
G1
G2
G3
S3
