Medium
d.77 on Vaillant Home Combi

Your boiler is taking longer than expected to heat your hot water cylinder, which usually suggests a sensor reading issue or a struggle to transfer heat 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

Max.cylinderreheating

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 33.
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 →d.71View →F.77View →

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