Boiler displays E13 and shuts down, often associated with flue or condensate issues
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Switch off the boiler and do not attempt to run it with a suspected flue fault. Risk of carbon monoxide exposure.
User checks:
- Visually inspect the external flue terminal for obstructions and remove any debris.
- Check that the condensate pipe is not frozen or blocked; thaw gently if frozen and ensure it discharges freely.
Engineer checks:
- Inspect the flue system for correct assembly, slope, and integrity as per Potterton instructions.
- Clean the condensate trap and check for correct reassembly and sealing.
- Test the flue temperature sensor and replace if readings are out of specification.
- Perform combustion analysis with a flue gas analyser and adjust or repair as required.
Any flue or combustion work must be carried out by a Gas Safe registered engineer.
Repair Difficulty
Required Part
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