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F5 FAULT CODE
Glow-worm

Overheat Fault

High Severity Engineer Required

The boiler has detected an overtemperature condition and shut down for safety. On older Glow-worm Betacom and Compact models.

Step-by-Step Fix Guide

  1. Step 1

    Turn off the boiler and allow to cool for 30 minutes

  2. Step 2

    Check system pressure and bleed radiators

  3. Step 3

    Reset once

  4. Step 4 Engineer only

    If fault returns, call a Gas Safe engineer to inspect the pump and heat exchanger

Gas Safe Reminder

Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.

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