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d.27 on Glow-worm Ultracom hxi

Your boiler is displaying an internal status code that indicates a software or configuration setting is not currently being used, which should not affect the daily operation of your heating or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Option Relay 1 Reserved for future use

From this model's manual
Verified against the Glow Worm Hxi System installation & service manual, page 36.
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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d.28View →d.29View →

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