High
E129 on Baxi Suprima 100

Your boiler is struggling to keep a flame lit while it tries to automatically adjust its settings, causing the system to shut down for 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

Safety error for frequently loss of flame with max correction during the ignition during Calibration Function.

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

E128View →E133View →128View →133View →

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