BoilerFaultCodesVaillant F.52 Fault Code
Also written as F52 — same fault.
The Vaillant F.52 fault code means: your boiler is struggling to accurately measure the air flowing into the burner unit which forces it to shut down to prevent unsafe operation.. It appears on 10 Vaillant models in our database.
Technical description: Contact fault mass flow sensor/Venturi
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 F.52 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vaillant F.52 fault code information on this page is sourced and cross-checked against the official Vaillant service / installation manuals for each affected model.
- Vaillant ecoTEC plus 612 manual (PDF)
- Vaillant ecoTEC plus 618 manual (PDF)
- Vaillant ecoTEC plus 624 manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 31 August 2026