Codes	Description
F1	Ignition fault
F3	Fan unable to reach ignition speed
F4	Ignition fault
F5	Overheat Fault
F6	Central heating flow thermistor
F9	Low water pressure Sensor
F10	Central return flow thermistor
F11	Flow and or return thermistor fault
F13	PCB memory or sensing fault
F14	Gas valve control defective
F15	E-bus voltage failure
F22	Low water pressure or ignition temperature rise too slow
F25	Circulation fault
F43	Generic error
F70	Software incompatible
F73	Unable to see pump activate
F77	Condensate pump error (optional)

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