P.13 Low

Vaillant P.13 Fault Code

Also written as P13 — same fault.

The Vaillant P.13 fault code means: your boiler is currently running a special setup routine to calibrate the gas pressure for liquid petroleum gas (lpg) operation.. It appears on 2 Vaillant models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Setting-up program: LPG (G30/31) mid setting point pressure
Typical repair cost £80-120 (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 P.13 fault code

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

Source

Vaillant P.13 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