Unigas H365X, Manual Of Installation - Use - Maintenance

Page: 29 / 116

PART III: OPERATION
29
Fig. 4 - Burner front panel
Fig. 5
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).
.
AIR FLOW AND FUEL ADJUSTMENT
(First) Start-up preliminary operations - gas supply
Recommended actions to be carried out in sequence:
1
Check the burner and all its components are installed correctly
2 Check that all electrical and mechanical parts are connected correctly
3 Check that there is water or other vector fluids in the generator
4 Check that the ventilation gates/dampers in the plant are open and the stack is free
5 Connect the gauges used to adjust and check pressures on the incoming line and on the head, air and fuel side.
6 Open the thermostatic series and the safety chain
7 Turn the main switch on the panel front with the "ON/OFF" selector to position "ON".
8 Check the phase and neutral position is correct
9 Open the manual shut-off valves slowly, in order to prevent any water hammers that might seriously damage valves and pressure
regulator
10 Check the sense of rotation of the electrical motors
11 Bleed the line, getting rid of all the air in the pipe as far as the main gas valve
WARNING! During commissioning operations, do not let the burner operate with insufficient air flow (danger of
formation of carbon monoxide); if this should happen, make the fuel decrease slowly until the normal combustion
values are achieved.
WARNING! the combustion air excess must be adjusted according to the values in the following chart.
Recommended combustion parameters
CO
2
(%) O
2
(%)
Fuel
Recommended (%) CO
2
Recommended (%) O
2
Natural gas 9 ÷ 10 4,8 ÷ 3
S1
B1
B2 B3 B4 B5
G1
G2
G3
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
A2 AZL..