High Lockout
E161 on Baxi Duo-tec/Megaflo

Your boiler has detected a problem with the fan that clears away waste gases, causing the system to shut down for safety.

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

Fan error

What causes this fault?

This fault occurs when the boiler's control board cannot detect that the fan is spinning at the correct speed to safely expel exhaust fumes. The most common reasons are a mechanical failure within the fan motor itself or a communication issue caused by a faulty circuit board and wiring. Without a functioning fan, the boiler cannot safely light the flame and will shut down immediately.

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

E164View →

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