P.06 Low

Vaillant P.06 Fault Code

Also written as P06 — same fault.

The Vaillant P.06 fault code means: your boiler has been manually set to a maintenance mode for filling or draining the system, meaning it is currently paused and will not provide heating or hot water.. It appears on 23 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: Filling mode: The prioritising diverter valve is moved to the mid-position. The burner and pump are switched off (to fill or drain the product).

What causes the Vaillant P.06 fault?

This code appears because the boiler has been manually put into a specific service mode by a person interacting with the control panel. It is triggered when someone is intending to fill, drain, or bleed the system, which causes the boiler to pause its normal operation for safety. The boiler hasn't broken; it is simply waiting in a 'standby' state while maintenance tasks are performed.

DIY fix possible

Navigate to the boiler's digital menuExit the 'Check Program' or 'Filling' settingsRestart the boiler to return it to normal operation

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Vaillant models that show the P.06 fault code

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

Source

Vaillant P.06 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 31 August 2026