📋 Key Takeaways
- 1.What it means: Abnormal flue temperature.
- 2.What to do: Do not operate. Gas Safe engineer immediately.
- 3.DIY or engineer? A Gas Safe engineer is required — do not attempt to repair gas components yourself.
Fault Code F7: Flue gas thermostat
Abnormal flue temperature.
This fault requires a Gas Safe registered engineer to diagnose and repair. Do not attempt to reset the boiler repeatedly. It is illegal to carry out gas work without Gas Safe registration.
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The component-level repair guide for this fault code is available to Pro subscribers — designed for Gas Safe engineers and heating professionals.
- ✓Exact components to test and replace
- ✓Pressure and temperature diagnostic values
- ✓Common misdiagnosis warnings
- ✓Printable fault diagnosis sheet
- ✓Direct links to genuine spare parts
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