High
Lock-out signal lamp OFF on Biasi Riva Compact 24S

Your boiler is failing to start up for central heating even though no warning lights are showing, meaning the ignition sequence is failing at various stages.

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

The burner doesn't light in c.h. mode. Fan still. The burner doesn't light in c.h. mode. Fan turns. The burner doesn't light in c.h. mode. Fan doesn't turn.

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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