| E35 | Parasitic flame detected Info: The boiler detects a flame even when the gas valve should be closed. Faulty gas valve or flame sensor. | Boiler | |
| E40 | Door lock fault Info: The door is not closed properly, or the door lock mechanism has failed. | Washing Machine | |
| E61 | Water is not heating Info: Heating element failure or a fault with the temperature sensor (NTC). | Washing Machine | |
| E90 | Appliance unresponsive, communication error Info: Communication fault between the main control board and other electronic components. | Washing Machine | |
| F01 | Oven is completely dead or unresponsive Info: Failure of the main electronic control board (PCB). | Oven | |
| F1 | Overheat lockout Info: Lack of water circulation causing the boiler to overheat. Could be a seized pump or closed valves. | Boiler | |
| F2 | No hot water Info: Domestic Hot Water (DHW) temperature sensor (NTC) is faulty. | Boiler | |
| F03 | Oven overheating or not heating correctly Info: The oven temperature sensor (NTC) has an open circuit, meaning it's broken or disconnected. | Oven | |
| F3 | No central heating Info: Central Heating (CH) temperature sensor (NTC) is faulty. | Boiler | |
| F4 | Boiler fails to ignite Info: Multiple ignition attempts have failed. Can be due to gas supply, electrode, or flame sensor issues. | Boiler | |
| F05 | Door lock mechanism error Info: Fault with the door locking system, common during or after a pyrolytic cleaning cycle. | Oven | |
| F5 | Air pressure switch or fan fault Info: The air pressure switch has not operated correctly, indicating a fan or flue issue. | Boiler | |
| F6 | Poor cleaning performance, usually on one rack Info: Fault with the diverter valve, which alternates water flow between the upper and lower spray arms. The valve may be stuck or its motor has failed. | Dishwasher | |
| F08 | No heat from heating element Info: The heating element relay on the main board has failed. | Oven | |
| F8 | Oven door will not lock for self-clean cycle, or will not unlock after Info: There is a fault with the motorized door lock assembly. The mechanism could be jammed, or the motor/switch has failed. | Oven | |
| F11 | Wash motor or circulation pump error Info: The main circulation pump is blocked by debris or has failed. | Dishwasher | |
| F12 | No water entering the appliance Info: Water inlet valve is closed, hose is kinked, or the inlet valve solenoid has failed. | Dishwasher | |
| F22 | Low water pressure warning Info: The heating system pressure is below the minimum required level (typically 0.5 bar). | Boiler | |
| F37 | Incorrect system water pressure Info: Pressure is either too low or too high, or the pressure sensor is faulty. | Boiler | |
| H | High temperature alarm, flashing display or beeping Info: The internal temperature of the refrigerator or freezer is too high. This can be caused by a door left open, a power outage, or a cooling system fault. | Refrigerator | |
| i20 | Water left in the bottom of dishwasher after cycle Info: Drain filter or drain hose is blocked. | Dishwasher | |
| i30 | Dishwasher has stopped and may be beeping continuously Info: Anti-flood device has been activated due to a leak in the base of the machine. | Dishwasher | |
