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

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 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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