Medium
d.71 on Vaillant Turbomax Plus

Your boiler has detected that the water temperature is being restricted to a limit that prevents it from heating your home or water effectively.

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

Maximum target value for heating system flow temperature

From this model's manual
Verified against the Vaillant Turbomax Plus installation & service manual, page 39.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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d.70View →F.01View →F.02View →

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