Medium
S.54 on Vaillant Turbomax Plus 824/828E

Your boiler has temporarily entered a cooling-down pause because the water inside is heating up too quickly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Delay mode due to flow temperature gradient too steep (approx 10 mins.)

From this model's manual
Verified against the Vaillant Turbomax Plus 824 828e 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 that at least two or three radiator valves are fully openEnsure the central heating system pressure is between 1.0 and 1.5 barBleed all radiators to remove any trapped airWait up to 20 minutes for the internal timer to reset naturally

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