Vokera water heater displays code 13, appliance shuts down on flue over-temperature or sensor fault
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: Turn off the heater and do not operate it until the flue and combustion have been checked. Risk of overheating and CO.
Owner checks:
- Visually inspect the external flue terminal for obstructions.
- Ensure that no combustible materials are stored close to the flue or appliance casing.
Engineer checks:
- Test the flue temperature sensor resistance and replace if out of specification.
- Inspect the flue system for blockages, incorrect slope, or damage.
- Check combustion using a flue gas analyser and adjust as required.
- Verify secure wiring connections between the sensor and PCB.
This is a combustion safety fault; only qualified engineers should perform internal diagnostics.
Repair Difficulty
Required Part
We may earn a commission from links on this page.