High Lockout
b65 on Vokera Pinnacle

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.

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

Insufficient fan speed for ignition

What causes this 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 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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