Medium
E091 on Vokera Evolve S

Your boiler has detected that the internal heating surfaces are becoming obstructed, which prevents it from transferring heat effectively and could cause it to stop working soon.

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

clean primary heat exchanger

From this model's manual
Verified against the Vokera Evolve S installation & service manual, page 10.
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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