Medium
S.54 on Vaillant Turbomax Plus 828

Your boiler has paused because it is heating up much more quickly than it should, suggesting that water isn't moving through the system properly.

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 and internal bypass valves are fully openCheck the boiler pressure gauge and top up to 1.5 bar if it is lowBleed any trapped air from your radiators

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Related fault codes

S.53View →F.20View →F.24View →

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