Low
S.28 on Vaillant Thermocompact

Your boiler is currently in a short waiting period to prevent it from switching on and off too frequently, which protects its internal components from excessive wear.

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

Anti cycling mode (warm start)

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 →

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