FAULT CODES

None

Fault code	Cause	Action (click on appropriate action)
10	Short circuit, outside temperature sensor	Check the outside temperature sensor and lead
18	Lead break, outside temperature sensor	Check the outside temperature sensor and lead
30	Short circuit, boiler water temperature sensor	Check boiler water temperature sensor
38	Lead break, boiler water temperature sensor	Check boiler water temperature sensor
50	Cylinder demand terminal box fault	Check terminal box connections & replace terminal box if required.
58	Cylinder demand terminal box fault	Check terminal box connections & replace terminal box if required.
60	Short circuit, return temperature sensor	Check the return temperature sensor
68	Lead break, return temperature sensor	Check the return temperature sensor
A9	Communication error, Open Therm device	Check connections and lead; replace Open Therm device if required.
b0	Short circuit, flue gas temperature sensor	Check sensor
b8	Lead break, flue gas temperature sensor	Check sensor
E5	Internal fault	Check the ionisation electrode and connecting cables
F0	Internal fault	Control unit
F1	Max. flue gas temperature exceeded	Check heating system fill level, circulation pump & system
F2	Temperature limiter has responded	Check system fill level, pump & system. temperature limiter
F3	Flame signal is present at burner start	Check ionisation electrode and connecting cable
F4	No flame signal detected	Check ignition operation
F8	Fuel valve closes too late	Check gas train, check both control paths
F9	Fan speed too low during burner start	Check fan, cables and power supply to fan; check fan control
FA	Fan idle state not reached	Check fan, cables and power supply to fan; check fan control
FC	Electrical fan control (control unit) faulty	Check fan connecting cable, control unit
FD	Fault, burner control unit	Check ignition electrodes, cables, interference (EMC) field
FF	Fault, burner control unit	Check ignition electrodes, cables, interference (EMC) field