Boiler displays E06, hot water temperature fluctuates or boiler shuts down during DHW draw-off.
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 power and close the cold water inlet isolation valve before removing any DHW components.
User-level checks:
- Reset the boiler and test hot water at a tap; note if E06 reappears quickly.
- Ensure cold inlet and hot outlet isolation valves under the boiler are fully open.
Technical checks (qualified personnel):
- Locate the DHW NTC sensor on the plate heat exchanger or DHW outlet manifold.
- Measure sensor resistance and compare with manufacturer’s NTC chart.
- Inspect for limescale build-up in the DHW heat exchanger that may cause local overheating; descale if necessary.
- Repair or replace damaged wiring or connectors.
- Replace the DHW NTC sensor if readings are incorrect or intermittent.
After repair, run hot water for several minutes to confirm stable temperature and absence of error codes.
Repair Difficulty
Required Part
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