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F33 FAULT CODE
Glow-worm

Flue Gas Recirculation

High Severity Engineer Required

Flue gases are being drawn back into the air intake, affecting combustion.

Step-by-Step Fix Guide

  1. Step 1

    Check flue terminal position and clearances

  2. Step 2 Engineer only

    A Gas Safe engineer should inspect the flue installation

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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