High
F0 on Worcester Bosch 35 RSF

Your boiler's computer is having trouble communicating with its internal components, causing the system to shut down for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Internal error – electrical connector contacts or programmer interface module – check ignition leads are not loose.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

EAView →C6View →

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