High
87 on Alpha C25 Xtraflame

Your boiler has detected an internal safety fault in the part that manages the gas supply, meaning it has shut down to prevent unsafe operation.

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

Block - gas valve control - A malfunction of one of the components that control the gas valve has been detected

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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