Unigas K750A, Руководство пользователя

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PART III: OPERATION
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Fig. 1 - 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..
Fig. 2
Gas operation

Check the gas feeding pressure is sufficient (signalling lamp G3 on).

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.
NOTE: if the burner is fitted with Dungs VPS504, the pre-purgue phase starts once the gas proving system is successfully performed.
Since the pre-purgue phase must be carried out with the maximum air rate, the control box drives the actuator opening and when the
maximum opening position is achieved, the pre-purge time counting starts.

At the end of the pre-purge time, the actuator drives the complete closing (ignition with gas position) and, as this is achieved the
ignition transformer is energised (LED
B4 is on); the gas valves open.

Few seconds after the valves opening, the transformer is de-energised and lamp B4 turns off.

The burner is now operating, meanwhile the actuator goes to the high flame position and, after some seconds, the two-stage ope-
ration begins; the burner is driven automatically to high flame or low flame, according to the plant requirements.
Operation in high or low flame is signalled by lamp B2 on the frontal panel.
AIR FLOW AND FUEL ADJUSTMENT
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.
S1
B1
B2
B3 B4
B5
G1
G2
G3
S3
A1
A2