F.330 High

Vaillant F.330 Fault Code

Also written as F330 — same fault.

The Vaillant F.330 fault code means: your boiler has detected that the water pump responsible for circulating heat around your home is not communicating correctly, meaning your heating and hot water will not work.. It appears on 3 Vaillant models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Fault in the electrical connection for the pump. The pump is not responding to commands during the hydraulic test.
Typical repair cost £200-450 (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 F.330 fault code

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

Source

Vaillant F.330 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 7 July 2026