| F.70 | Invalid boiler identification. | It usually appears after simultaneously replacing the display (UI) and the main PCB without reconfiguring the product code/DSN or with incorrect coding resistance. Verify by entering the service menu and readjusting the product code; if it persists, check/replace the display with the correct reference. |
| F.707 | It is not possible to establish any communication between the display and the PCB. | eBUS communication fault between the display board and the main PCB (cable/connectors or display module faulty). Check 5 V and eBUS signal at the connector, inspect/replace the cable, and test with another screen. |
| F.363 | EEPROM of the display: error during read/write test. | Memory of the display board damaged or with corrupted data. Verify by retrying the test from service; if it reappears, replace the display. |
| F.18 | User interface fault (display). | Fault in the display/interface board. Confirm power supplies and bus; test with a known-good display or replace the module. |
| F.20 | Software incompatibility (incorrect user interface or main PCB; incorrect product code). | Non-corresponding or incorrectly coded display/UI causes incompatibility with the PCB. Verify and correct the product code/DSN; if it does not match, install the correct display. |
| 12 | User interface fault (display/remote control). | In older models with numerical codes, error 12 points to the interface/display module. Check power supply and wiring and test with another display; if the issue persists, replace the display PCB. |
