Ideal Boiler Codes	Possible Cause
C0	BCC Activation Fault.
C2	BCC Fault.
F1	Low Water Pressure.
F2	Flame Loss.
F3	Fan Fault.
F4	Flow Thermistor.
F5	Return Thermistor.
F6	Outside Sensor Failure.
F7	Low Mains Voltage.
F9	Unconfigured PCB.
L1	Flow Temperature Overheat or No Water Flow.
L2	Flame Loss.
L5	5 Boiler Resets in 15 Minutes.
L6	False Flame Lockout.
0	The boiler is in standby mode awaiting either a central heating call or hot water demand.
C	The boiler has a call for central heating but the appliance has reached the desired temperature set on the boiler.
C	The boiler is in operating in central heating mode.
D	The boiler has a call for hot water but the appliance has reached the desired temperature set on the boiler.
D	The boiler is operating in hot water mode.
F	The boiler is operating in frost mode.

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