Heatline S.06 Fault Code
Also written as S06 — same fault.
The Heatline S.06 fault code means: your boiler is currently running its internal fan to safely vent any remaining gases after the burner has turned off, which is a normal part of the shutdown process.. It appears on 8 Heatline models in our database.
Technical description: Post run fan
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 S.06 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Heatline S.06 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