High Lockout
E00-716 on Worcester Bosch 24/28CDi II RSF

Your boiler has detected a serious problem with the fan that safely removes exhaust gases, meaning the system has shut down for your 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 Assembly WHS

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 clear exhaust fumes. The most common reasons are a mechanical failure within the fan motor itself, loose electrical connections, or a fault on the main circuit board that prevents it from sending power to the fan.

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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