C.I.B. UNIGAS
- M039231CB
29
z
Refit the transparent plastic cover on the pressure switch.
Calibration of low gas pressure switch
As for the gas pressure switch calibration, proceed as follows:
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Remove the transparent plastic cap.
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While the burner is operating at the maximum output, test the gas pressure on the low gas pressure switch port.
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Slowly close the manual shut-off valve (placed upstream the pressure switch, see gas train installation diagram), until the measu-
red pressure is reduced by 50%. Pay attention that the CO value in the flue gas does not increase.
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Check that the burner is operating correctly.
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Screw down the pressure switch adjusting ring nut until the burner lockout.
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Fully open the manual shut-off valve.
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Refit the transparent plastic cover on the pressure switch.
PGCP Gas leakage pressure switch (witn Siemens LDU burner control/Siemens LMV Burner Management
System)
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remove the pressure switch plastic cover;
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adjust the PGCP pressure switch to the same value set for the minimum gas pressure switch;
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replace the plastic cover.
Adjusting the high gas pressure switch (when provided)
To calibrate the high pressure switch, proceed as follows according to its mounting position:
1
remove the pressure switch plastic cover;
2
if the maximum pressure switch is mounted upstreaam the gas valves: measure the gas pressure in the network, when flame is off;
by means of the adjusting ring nut
VR
, set the value read, increased by the 30%.
3
if the maximum pressure switch is mounted downstream the “gas governor-gas valves” group and upstream the butterfly valve:
light the burner, adjust it according to the procedure in the previous paragrph. Then, measure the gas pressure at the operating
flow rate, downstream the “gas governor-gas valves” group and upstream the butterfly valve; by means of the adjusting ring nut
VR
, set the value read on step 2, increased by the 30%;
4
replace the plastic cover.
