Ignition indicator High

Vaillant Ignition indicator Fault Code

Also written as IGNITIONINDICATOR — same fault.

The Vaillant Ignition indicator fault code means: your boiler is struggling to light the burner, meaning it is currently unable to produce heat or hot water.. It appears on 2 Vaillant models in our database.

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: The gas valve will open and sparking will commence at the burner. The ignition indicator will illuminate.
Typical repair cost £120-250 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Vaillant models that show the Ignition indicator fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Vaillant Ignition indicator fault code information on this page is sourced and cross-checked against the official Vaillant service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026