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3064810_201804
41. Troubleshooting
Fault
code
Fault
Possible causes
Remedy
01
HLSC excess temp.
High limit safety cut-out (thermostat) has
responded
Temperature at the heat exchanger
cover has exceeded 185 °C
Combustion chamber contaminated
High limit safety cut-out:
- Check cables and plugs
- If electrical connection OK and no func-
tion: Replace HLSC
Combustion chamber:
- If combustion chamber is contaminated,
clean or replace combustion chamber
Check heating circuit pump
Vent the system
Press reset button
02
TL excess temp.
One of the temperature sensors
eHLSC1 or eHLSC2 on the combustion
chamber has exceeded the high limit
safety cut-out limit (108 °C)
System pressure
Air in heating circuit
Pump
Check system pressure.
Vent heating circuit.
Temperature limiter (eHLSC):
- Check cables and plugs.
- If OK and no function, replace the eHLSC.
Pump:
- Check if pump is running.
- If not, check cables and plugs.
- If electrical connection OK and no func-
tion: Replace the pump.
Press reset button.
03
dt flow drift
Temperature differential between
temperature sensors eHLSC1 and
eHLSC2 > 6 °C at the combustion
chamber
eHLSC:
- Faulty, replace eHLSC
Press reset button.
04
No flame established
When the burner starts, no flame forms
by the end of safety time
Monitoring electrode faulty
Ignition electrode faulty, ignition
transformer faulty
Gas supply
HG44 curves offset
Gas valve
Gas valve has been replaced
Gas condensing boiler contaminated
Gas supply:
- Check the gas train (gas valve open?).
Ionisation electrode:
- Check the position and condition of the
electrode, adjust or replace if necessary.
Ignition electrode:
- Check the position of the ignition elec-
trode and adjust if necessary. Check the
ignition transformer and wiring.
HG44 curves offset:
- Set HG44 to standard value
Gas valve:
- Check that the gas valve opens; if not,
check cables and plugs and repeat test.
- If faulty, replace the gas valve.
Press reset button.
- Set HG44 to standard value after replac-
ing the gas valve.
Summary of Contents for CGB-2 Series
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