PART IV: MAINTENANCE
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8.6 Replacing the detection electrode
To replace the detection electrode, proceed as follows:
1
remove the combustion head according to the procedure on paragraph “Removing the combustion head”;
2
by means of an allen key, loose the fixing screws of the detection electrode
ER
and replace it;
3
replace the combustion head.
8.7 Checking the detection current (natural gas)
To check the detection signal follow the scheme in the picture below. If the signal is less than the value indicated, check the position of
the detection electrode or detector, the electrical contacts and, if necessary, replace the electrode or the detector.
8.8 Checking the detection current (L.P.G.)
To check the detection signal follow the scheme in the picture below. If the signal is less than the value indicated, check the position of
the detection electrode or detector, the electrical contacts and, if necessary, replace the electrode or the detector.
ATTENTION: avoid the electrode to get in touch with metallic parts (blast tube, head, etc.), otherwise the boiler
operation would be compromised. Check the electrode position after any intervention on the combustion head.
Device
Flame detector
Minimum detection signal
Siemens LMV2x/3x
Ionization probe
4 µA (values on display: 30%)
Device
Flame detector
Minimum detection signal
Siemens LMV2x/3x
QRA
70 µA (intensity of flame >24%)
ER
ER
Protective earth PE
Ionization probe (ION)
QRB.../ QRC... signal voltage
QRB... GND
1
2
3
4
5
L
X10-05
QRA... (-)
QRA... (+)
1
2
X10-06
+
