High
F.57 on Vaillant ecoTEC exclusive

Your boiler has detected that a key ignition component is wearing out, meaning it is struggling to reliably start the flame needed to heat 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

Fault:Measuringprogram Activecomfortprotectionmodehasdetectedaregulationfault – Ignitionelectrodehighlycorroded

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

F.28View →F.29View →

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