Medium
S.54 on Vaillant Turbomax Plus VUW 242EH

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 all radiator valves are fully openEnsure the boiler pressure is between 1.0 and 1.5 barRemove any obstructions from magnets or external system filtersBleed any air from the radiators

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Related fault codes

S.53View →F.22View →

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