Codes	Description
F1	Ignition fault
F2	Fan
F3	Fan unable to reach ignition speed
F4	Ignition fault
F5	Overheat Fault
F6	Central heating flow thermistor
F7	Domestic hot water thermistor
F8	Tank thermistor (N/A For this appliance)
F9	Water pressure sensor fault (please contact GW technical department for further information
F10	Central return flow thermistor
F11	Main board connection fault
F12	Connection fault between main pcb and display pcb
F13	Main pcb connection fault
F14	Central heating flow temperature > 95 degrees
F15	Gas valve stepper motor fault
F16	Flame detection fault
F17	Power supply is less than 170v
F18	User interface fault
F19	Central heating thermistor unplugged
F20	Software incompatibility
F24	Central heating return temperature > 90 degrees
F25	Poor circulation
F26	Poor circulation

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