Heatline F05 Fault Code
The Heatline F05 fault code means: your boiler is struggling to clear exhaust fumes safely, so it has turned itself off to prevent any risk of fumes entering your home.. It appears on 2 Heatline models in our database.
Technical description: Air pressure switch failure / Fan failure
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Heatline models that show the F05 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Heatline F05 fault code information on this page is sourced and cross-checked against the official Heatline service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026