High Lockout
E161 on Potterton Promax

Your boiler has stopped working because the fan used to clear out waste gases is not spinning at the correct speed or has failed to 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 fault

What causes this fault?

This fault occurs when the boiler's control system detects that the fan is not spinning fast enough to safely clear waste gases from the flue. The most common reasons are a buildup of dirt on the fan blades, moisture causing the motor to seize, or a communication failure between the fan and the main circuit board.

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

E160View →E133View →E110View →

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