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F29 FAULT CODE
Glow-worm

Flame Loss During Operation

Medium Severity DIY Check Possible

The boiler ignited but then lost the flame during operation.

Cold Weather Note

Frozen condensate is the primary winter cause.

Step-by-Step Fix Guide

  1. Step 1

    Check condensate pipe for frost

  2. Step 2

    Thaw if frozen, then reset

  3. Step 3

    If fault persists in warm weather, call a Gas Safe engineer

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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