High
E01 on Biasi ActivA 25C

Your boiler has failed to light the gas flame, meaning it has shut itself down for safety and cannot provide 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

Ignition failure or false flame detection

From this model's manual
Verified against the Biasi/Biasi Activa Service Manual July 2009 Pdf installation & service manual, page 13.
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

E02View →E06View →

All 17 fault codes on the ActivA 25C

Seeing a different code? Every code this model can display, in one place.

E23Er01Er02Er03Er04Er05Er06Er07Er08Er09Er10Er11Er14Er14+RESETEr99Li01

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