Low
S.26 on Vaillant ecoTEC

Your boiler is simply finishing its cooling cycle to move leftover heat away from the inside of the unit, which is a normal part of the shutdown process after the heating or hot water has been running.

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

Fan over run

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.27View →S.28View →

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