High
F0 238 on Worcester Bosch 24 RSF

Your boiler has detected an internal electrical communication error between the main controller and the gas supply unit, meaning it cannot safely ignite.

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

Gas valve or control box error – gas valve coils need checking

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 →C6View →

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