Ariston water heater shows E11; unit may heat only at maximum or not regulate power correctly.
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: Disconnect power at the breaker. High voltages are present on the control board; if you are not trained, do not attempt board-level repairs.
- Visual inspection: Remove the cover and inspect the control board for burnt components, cracked solder joints, or melted connectors in the power section.
- Check wiring to elements: Ensure each heating stage is wired according to the Ariston wiring diagram. Miswiring can cause E11.
- Measure element current (advanced): A technician can use a clamp meter to verify that current draw matches expected values for each stage.
In most cases, an E11 fault requires replacement of the entire control board with an OEM Ariston board. This should be done by a qualified technician to ensure safe operation.
Repair Difficulty
Required Part
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