BoilerFaultCodesVokera b65 Fault Code
Also written as B65 — same fault.
The Vokera b65 fault code means: your boiler's fan is not spinning fast enough to clear the pipes, which prevents the system from safely lighting the gas to provide heating or hot water.. It appears on 1 Vokera model in our database.
Technical description: Insufficient fan speed for ignition
What causes the Vokera b65 fault?
This fault occurs when the boiler's management system detects that the fan is rotating too slowly to safely expel exhaust gases. The most common reasons are a buildup of debris or dust hindering the motor, a failing electronic component on the fan itself, or the main control board failing to send the correct voltage to the motor.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Vokera models that show the b65 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vokera b65 fault code information on this page is sourced and cross-checked against the official Vokera service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026