High
F0 on Alpha E-Tec Plus

Your boiler's electronic settings do not match the physical flue pipe installed, needing a quick adjustment to confirm the pipe length is set correctly for your home.

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

Flue length parameter - should be changed for flue lengths over 4.5 m

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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