Biasi LD3 Fault Code
The Biasi LD3 fault code means: your boiler has detected an internal electrical communication error or a fault with the main circuit board.. It appears on 2 Biasi models in our database.
Technical description: Operation light 3 (as seen in wiring and voltage diagrams)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Biasi models that show the LD3 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Biasi LD3 fault code information on this page is sourced and cross-checked against the official Biasi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026