Codes	Description
F00	No fault
F02	Air flow fault
F04	Ignition fault – flame detection
F05	Overheating
F06	Central heating thermistor/wiring fault
F07	Domestic hot water thermistor/wiring fault
F08	Storage vessel thermistor/wiring fault
F09	System pressure sensor fault
F10	Fan fault
F11	Poor circulation
F12	User interface fault
F13	Main pcb fault
F14	Central heating flow temperature > 97 degrees
F15	Gas mechanism fault
F20	Communication fault

As a member check out these Key Areas