B-2 Low

Ferroli B-2 Fault Code

Also written as B2 — same fault.

The Ferroli B-2 fault code means: your boiler is correctly registering that a hot tap is turned on and is preparing to provide hot water.. It appears on 2 Ferroli models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Hot water tap open - D.H.W. flowmeter (136) contact closed

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Ferroli models that show the B-2 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ferroli B-2 fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026