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

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

Technical description

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

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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S.53View →F.22View →

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