Low
S.08 on Vaillant Turbomax Plus

Your boiler is perfectly fine and is simply taking a short, scheduled break to prevent the heating system from overheating.

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.

What the manual says

Manufacturer manual

Anti cycling mode (heating operation)

From this model's manual
Verified against the Vaillant Turbomax Plus installation & service manual, page 38.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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