High
F0 290 on Worcester Bosch 35 RSF

Your boiler’s internal computer has encountered a critical error, meaning the main control system is unable to communicate with its internal components.

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

Control box is defective – HCM needs checking as it might not be inserted properly or need replacing

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 →F7View →FDView →

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