High Lockout
b28 on Vokera Pinnacle

Your boiler has stopped working because the internal fan, which safely clears waste gases, is not spinning or communicating with the main control board.

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

No signal from fan

What causes this fault?

This fault occurs when the boiler's control board sends a command for the fan to start, but detects that the fan isn't spinning at the required speed. The most common reason is the fan motor itself failing after years of use, though it can also be caused by loose electrical connections or a fault on the main circuit board. Because the fan is responsible for safely removing exhaust gases, the boiler will refuse to ignite as a safety precaution.

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

b 18View →b 19View →

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