Glow-worm 18sxi Fault codes & diagnostics

1 fault code with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Gas 2004-present
GC Number 41-047-72
Download the Glow-worm 18sxi manualThe official installation and service manual (PDF), the document these fault codes were read from. PDF

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Versions & GC numbers

Which version do you have?

The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.

GC number Appliance (register name) Produced
41-047-72 18sxi 2004–present

Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.

Fault codes

All 1 documented codes

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F5

Your boiler has temporarily stopped working because trapped air inside the system has caused it to get too hot.

High Engineer only £90-180

Parts commonly replaced

  • Overheat thermostat
  • Automatic air vent
  • Circulating pump

Related codes

Full explanation for F5
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