High Lockout
E83458 on Potterton Powermax HE

Your boiler has detected a communication failure or a mechanical fault with the fan, meaning it cannot safely clear exhaust fumes and will not start.

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 c/w ‘O’Ring & Gasket

What causes this fault?

This fault occurs when the boiler's main control board loses touch with the fan or detects that it isn't spinning at the correct speed. The most common reason is that the fan motor has burnt out or seized, but it can also be caused by loose wiring connections or a failing control board that can no longer send 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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Related fault codes

E01View →

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