Unigas E150X, Manual Of Installation - Use - Maintenance

Page: 26 / 116

PART III: OPERATION
26
Integrated proving system (burners equipped with LME7x, LMV, LDU)
ADJUSTING AIR AND GAS FLOW RATES
Adjustments - brief description

The air and fuel rates adjustments must be performed at the maximum ouptput first (“high flame”): see the LMV related manual.

Check that the combustion parameters are in the suggested limits.

Check the flow rate measuring it on the counter or, if it was not possible, verifying the combustion head pressure by means of a dif-
ferential pressure gauge, as described on par. “Measuring the gas pressure in the combustion head”.

Then, adjust the combustion values by setting the “gas/air” ratio” curvepoints (see the LMV related manual).

Set, now, the low flame output (according to the procedure described on the “Siemens LMV manual”) in order to avoid the low
flame output increasing too much or that the flues temperature gets too low to cause condensation in the chimney.
(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
Fuel
Recommended (%) CO
2
Recommended (%) O
2
Natural gas 9,0 ÷ 10 3,0 ÷ 4,8
LPG 11 ÷ 12 2.8 ÷ 4,3
This paragraph describes the integrated proving system operation sequence:

At the beginning both the valves (EV1 and EV2) must be closed.

Test space evacuating: EV2 valve (burner side) opens and keep this position for a preset time
(td4), in order the bring the test space to ambient pressure.Test atmospheric pressure: EV2 closes
and keep this position for a preset time (test time td1). The pressure switch PGCP has not to detect
a rise of pressure.

Test space filling: EV1 opens and keep this position for a preset time (td3), in order to fill the test
space.

Test gas pressure: EV1 closes and keep this position for a preset time (td2). The pressure switch
PGCP has not to detect a pressure drop down.
If all of the test phases are passed the proving system test is successful, if not a burner lockout
happens.
On LMV5x and LMV2x/3x and LME73 (except LME73.831BC), the valve proving can be
parameterized to take place on startup, shutdown, or both.
On LME73.831BC the valve proving is parameterized to take place on startup only.
PS
EV1 EV2
/
EV2
EV1
PGCP