Boiler displays E25, may be associated with incorrect configuration or incompatible accessories.

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

Incorrect installer settings, Wrong boiler type selected in menu, Incompatible accessory configuration, Corrupted parameter memory

Safety: Only trained personnel should change installer-level parameters.

Check user settings: Ensure basic settings (heating mode, DHW mode) are correct in the user menu.
Restore default parameters: A technician can access the installer menu and restore factory defaults, then reconfigure according to the installation.
Verify accessories: Confirm that connected accessories (sensors, tanks, controllers) match the configuration selected.
Professional service: If E25 persists, the control PCB may need reprogramming or replacement.

Hard 4/5

Control PCB (Configuration Memory)

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