Error code	Possible fault
E09	Gas valve wiring fault
E10	Outdoor sensor error
E15	Gas valave connection fault
E20	Central heating thermistor sensor fault
E28	Flue thermistor fault
E40	Central heating return thermistor fault
E50	Domestic hot water sensor fault
E53	Flue obstruction
E55	Calibration required
E78	Water pressure sensor fault
E83/84/85/86/87	No communication between room controller and boiler
E92	Combustion test alarm during auto-setting
E109	Poor circulation
E110	Boiler overheat tripped
E117	System pressure high (>2.9 bar)
E118	System pressure low (<0.5>
E125	Primary water circulation fault
E128	Loss of flame during operation
E129	Loss of flame during calibration
E130	Flue thermostat sensor tripped (lockout)
E133	Ignition fault
E135	Internal error
E154	Primary flow fault
E160	Fan fault
E270	Dry fire
E317	Wrong power supply (HZ)
E321	Hot water thermistor fault
E384	Flame detected when gas valve off (false flame)
E385	Low voltage (less than 195v)

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