Worcester - British Gas 542 Boiler Fault Codes

Code	Description	Remedy
A1	Pump has run dry	Check system pressure, add water and bleed system as necessary.
A7	Hot water NTC sensor defective	Check hot water NTC sensor and connecting lead for circuit breaks/short circuits
b1	Code plug not detected	Insert code plug correctly, test and replace if necessary
C6	Fan speed too low	Check fan lead and connector, and fan; replace as necessary
E2	CH flow NTC sensor defective	Check CH flow NTC sensor and connecting lead
E9	Safety temp. limiter in CH flow has tripped	Check system pressure, check safety temp. limiters, check pump operation, check fuse on pcb, bleed appliance.
EA	Flame not detected	Is gas cock turned on? Check gas supply pressure, power supply, igniter electrode and lead, ionisation sensing electrode and lead, flue duct and CO2 level.
F0	Internal error	Check electrical connector contacts, programmer interface module ignition leads are not loose; replace pcb if necessary
F7	Flame detected even though appliance switched off	Check electrode assembly, dry pcb. Flue clear?
FA	Flame detected after gas shut off	Check gas valve and wiring to gas valve. Clean condensation trap and check electrode assembly. Flue clear?
Fd	Reset button pressed by mistake	Press reset button again.