Boiler shows E6, often associated with hot water temperature issues on combi models, water may run too hot or cold.
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 before removing covers. Water may be hot; take care when working on DHW components.
User checks:
- Power cycle the boiler and test hot water at a tap. If E6 returns, stop using very hot water to avoid scalding.
Engineer checks:
- Locate the DHW NTC on the plate heat exchanger or DHW outlet and test its resistance.
- Inspect for limescale build-up restricting heat transfer; descale or replace the plate heat exchanger if necessary.
- Check wiring and connectors between the NTC and PCB.
- Replace the Worcester DHW NTC if readings are out of specification.
Sensor replacement is usually a moderate repair and restores stable hot water temperature control.
Repair Difficulty
Required Part
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