Medium
26.0 on Grant Vortex Eco

Your boiler is displaying a technical setting that indicates it is currently locked to its maximum heating capacity, which usually suggests a configuration or electronic control board error rather than a physical breakdown.

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 heat output (Kerosene) (kW)

From this model's manual
Verified against the Grant Vortex Eco installation & service manual, page 6.
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

27.0View →28.0View →

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