Low
S.08 on Vaillant ecoTEC plus aquaPLUS

Your boiler has reached its required temperature and is taking a short, planned break to prevent it from switching on and off too frequently.

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 Ecotec Plus Aquaplus 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.

DIY fix possible

Wait 15 to 20 minutes for the timer to finishCheck that your room thermostat is turned upEnsure your radiator valves are open to allow heat to dissipate

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