High
E128 on Potterton Sirius WH

Your boiler has detected that the flame inside has gone out unexpectedly while it was trying to heat your water or 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

Loss of flame during operation (the ionization current has fallen below the limit)

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

E133View →

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