Medium
GWB90 on Grant Vortex

This code indicates that the mounting bracket securing your boiler to the wall is either loose, damaged, or incorrectly installed, which could cause the unit to become unstable.

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

Wall bracket - standard

From this model's manual
Verified against the Grant Vortex installation & service manual, page 21.
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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