E15 appears and the thermostat reports a firmware update failure; some functions may be disabled.
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: Do not disconnect power during any subsequent firmware update attempts unless instructed by the manufacturer.
- Stable power and network: Ensure the thermostat and Tydom gateway have stable power and a reliable internet connection.
- Retry update: Use the Tydom app or thermostat menu to retry the firmware update. Follow on-screen instructions and wait until completion.
- Factory reset (if allowed): If the device offers a recovery or factory reset mode for firmware issues, follow the Delta Dore instructions to restore a stable firmware version.
If E15 remains and the thermostat is partially functional or bricked, contact a professional or Delta Dore support; the unit may need to be replaced.
Repair Difficulty
Required Part
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