Codes	Description
F1	Ignition fault
F2	Fan
F3	Fan
F4	Ignition fault
F5	Overheat Fault
F6	Central heating flow thermistor
F7	Domestic hot water thermistor
F8	Tank thermistor
F9	Water pressure sensor fault (please contact GW technical department for further information)
F10	Central return flow thermistor
F11	Main board connection fault
F12	User interface connection fault
F13	PCB memory or sensing fault
F14	Gas valve control defective
F16	Flame detection fault
F17	Power supply is less than 170v
F18	User interface fault
F19	Central heating thermistor unplugged
F20	Software incompatibility
F23	Water circulation fault
F24	Cental heating return temperature > 90 degrees
F25	Maximum temperature rise slope
F26	Maximum delta temperature

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