High
F1, F4 on Saunier Duval Semia Condens F30 E

Your boiler is failing to start because it cannot get the fuel it needs to produce a flame, meaning you currently have no heating or hot water.

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

Ignition fault, boiler fialed to light. No gas / Insufficient gas. Incorrect gas valve adjustment. Electrode ignition lead defect. Electrnic igniter defective. Check air inlet duct and connections to igniter unit

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

F2View →

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