Unigas PBY70, Manual Of Installation - Use - Maintenance

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C.I.B. UNIGAS - M039241CB
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9 Set the ignitor gas pressure switch PG (Fig. 17) at 50 mbar.
10 The nozzle supply pressure is already factory-set and must not be changed. Only if necessary, adjust the supply pressure as fol-
lows (see related paragraph); read the pressure on the oil preaaure gauge on Fig. 15 and act on on the pump governor adjusting
screw
VR (see Fig. 19 and description on page 21) as to get the nozzle pressure at 4-4.5bar (see step 7). If the required flow rate
is not reached, increase the feeding pressure by means of the Suntec TV governor (see Fig. 19)
11 The atomising air flow rate and pressure (see paragraph can be adjusted with the VA screw (Fig. 18). Too low a pressure produces
poor atomising with smoke in the flue. Too high a pressure produces instability and the flame can blow off.
12 To adjust the comburent 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.
13 If necessary, change the combustion head position: to let the burner operate at a lower output, move progressively back the com-
bustion head towards the MIN position, by turning clockwise the VRT ring nut. The graduated index ID shows the combustion head
shifting (each mark refers to 5mm).
Fig. 16 - Atomising air pressure switch
Fig. 17 - Gas pressure switch
Fig. 18 - Atomising air flow rate adjustment
Fig. 19 - Suntec TV Fig. 21 - Oil metering valve
PA
PG
VA
VR
VR
oil pressure gauge
compressed air ressure gauge
VRA
RA
TR