Medium
91 on Vokera Linea One

Your boiler has detected that grime or debris is building up inside the system and requires a professional service to ensure it continues to run safely and efficiently.

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

condensing heat exchanger cleaning requirement

From this model's manual
Verified against the Vokera Linea One installation & service manual, page 31.
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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