BoilerFaultCodesVaillant P.07 Fault Code
Also written as P07 — same fault.
The Vaillant P.07 fault code means: your boiler is currently running a self-cleaning mode to remove trapped air bubbles from the pipes and pump.. It appears on 14 Vaillant models in our database.
Technical description: Purging programme (manually started if the automatic purging programme does not start)
What causes the Vaillant P.07 fault?
This code appears when air has become trapped inside the boiler’s internal pipework or the central heating pump. It is usually triggered after the system has been drained and refilled, or if a leak has allowed air to enter the circuit. The boiler runs this specific cycle to force those air bubbles out, ensuring the components don't overheat or suffer from reduced water flow.
This is most common in autumn when homeowners turn their heating back on for the first time or after summer radiator maintenance has introduced air into the system.
DIY fix possible
Wait approximately 5 to 10 minutes for the programme to finish automaticallyEnsure your radiator valves are fully open to help air move through the systemCheck the boiler pressure gauge and top up to 1.5 bar if it has dropped
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Gas Safe Register →Vaillant models that show the P.07 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vaillant P.07 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