Low
S.28 on Vaillant ecoTEC plus aquaPLUS

Your boiler is taking a temporary break to prevent the system from turning on and off too frequently while it heats the internal hot water storage tank.

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 (store charging)

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

Check if any hot water taps are slightly open or drippingWait 15-20 minutes for the timer to count down and the boiler to restart automaticallyEnsure your thermostat is set to the desired temperature

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