Unigas K750A, Руководство пользователя

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PART III: OPERATION
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To adjust the air flow rate in the high flame stage , loose the RA nut and screw VRA as to get the desired air flow rate: moving the rod TR towards the
air damper shaft, the air damper opens and consequently the air flow rate increases, moving it far from the shaft the air damper closes and the air flow
rate decreases.
Note: once the procedure is perfomed, be sure that the blocking nut RA is fasten. Do not change the position of the air damper
rods.
9 If necessary, adjust the combustion head position (see the dedicated paragraph)..
10 The air and gas rate are now adjusted at the maximum power stage, go on with the point to point adjustement on the SV1 (gas
side) adjusting cam as to reach the minimum output point.
11 as for the point-to-point regulation, move the gas low flame microswitch a little lower than the maximum position (90°);
12 set the
TAB thermostat to the minimum in order that the actuator moves progressively towards the low flame position;
13 move the gas low flame microswitch to the minimum to move the actuator towards the low flame until the two bearings find the
adjusting screw that refers to the lower position: screw V1 to increase the rate, unscrew to decrease.
14 Move again the gas low flame microswitch towards the minimum to meet the next screw on the adjusting cam and repeat the pre-
vious step; go on this way as to reach the desired low flame point.
15 Now adjust the pressure switches.
Attention! if it is necessary to change the head position, repeat the air and gas adjustments described above.
VR
T
Siemens VGD..
8 acting on the pressure stabiliser of the valves group, adjust the gas flow rate in the high
flame stage as to meet the values requested by the boiler/utilisation:
- Siemens VGD valves group: remove cap T and act on the VR adjusting screw to increase or
decrease the pressure and consequently the gas rate; screwind VR the rate increases, unscrewing
it decreases (see next figure).
VRA
RA
TR
SV1
SV2
V1
Gas throttle valve open Gas throttle valve closed