High
20 on Halstead Dimplex System

Your boiler is failing to light the fuel needed to create heat, likely due to a problem with the internal gas control system.

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

No flame. Gas valve V1-V2 failure

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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