High
LD3 ON on Biasi Riva Compact 24S

Your boiler has stopped working because it failed to light or detected a safety issue, causing it to shut down for protection.

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

Lock-out - No flame / Safety thermostat / Flue temperature probe / Condensate trap full / Air pressure switch / Electronic control p.c.b.

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

LD1View →LD2View →

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