High
2925 V on Worcester Bosch 35 RSF

Your boiler has lost communication with the internal gas control system, meaning it cannot safely regulate the fuel it needs to stay lit.

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

Feedback from the modulating gas valve is too low

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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