High
F1 on Ferroli Tempra 12 18

Your boiler is unable to light its internal flame, which means 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.

What the manual says

Manufacturer manual

The burner fails to light. Check that the gas supply is open and that there is no air in the pipes.

From this model's manual
Verified against the Ferroli Tempra installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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 →F3View →F4View →

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