How much does it cost to fix Vaillant error code Er.2?

Typical repair cost for the Vaillant Er.2 fault is £120-250 including labour.

Er.2 High

Vaillant Er.2 Fault Code

Q: What does the Vaillant Er.2 fault code mean?

Your boiler is failing to light the flame or is unable to detect that it has successfully turned on, so it has shut itself down as a precaution.

Also written as ER2 — same fault.

The Vaillant Er.2 fault code means: your boiler is failing to light the flame or is unable to detect that it has successfully turned on, so it has shut itself down as a precaution.. It appears on 2 Vaillant models in our database.

Technical description: Ignition electrode / Flame sensing electrode

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 Er.2 fault code

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

Source

Vaillant Er.2 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