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F76 FAULT CODE
Heatline

Thermal Fuse Fault

High Severity Engineer Required

The thermal fuse on the heat exchanger has blown due to extreme overheating. The heat exchanger will need replacing.

Step-by-Step Fix Guide

  1. Step 1

    Call a Gas Safe engineer — the heat exchanger must be replaced

  2. Step 2 Engineer only

    Do not attempt to bypass the thermal fuse

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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