Low
S.13 on Vaillant Thermocompact

Your boiler is currently trying to light itself to provide hot water but is still in the middle of its startup process.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Ignition sequence (hot water operation)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

S.10View →S.11View →

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