Medium
E091 on Vokera Synergy System

Your boiler has detected that the main heating component is becoming blocked with debris or limescale and needs a professional service.

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 Synergy System installation & service manual, page 5.
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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Related fault codes

E020View →E021View →E024View →

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