Posted on: 28 March 2024
Does your Navien boiler have you stumped with a cryptic error code flashing on the display? Don’t panic! While boiler problems can be frustrating, many Navien fault codes point to simple fixes you can potentially tackle yourself.
If the fix seems beyond your DIY expertise, or the issue persists, our qualified Belfast-based engineers are just a call away at 02890 451010. We cover all of Northern Ireland to get your heating back on track quickly.
This guide will walk you through some of the most common codes:
When an error code appears on the front panel, refer to the following chart for a definition and possible remedy for the situation.
| Item | Error Code | Description | Reset |
|
Combustion |
E001 | Overheating of heat exchanger | Manual |
| E003 | Ignition failure | Manual | |
| E004 | False flame detection | Auto | |
| E012 | Flame loss | Manual | |
| E016 | Heat exchanger overheat | Manual | |
| E030 | Abnormal exhaust temperature | Manual | |
| E031 | Burner overheat | Manual | |
| E046 | Abnormal operation: Heat exchanger overheating sensor | Auto | |
| E047 | Abnormal operation: Exhaust thermostat | Manual/Auto | |
| E056 | Abnormal operation: Oil pump | Manual | |
| Air Circulation | E109 | Abnormal operation: Fan | Manual |
| E110 E | xhaust blockage (Condensate blockage) | Manual | |
| E127 | Abnormal operation: APS | Auto (Manual) | |
| E144 | Abnormal operation: Burner temperature sensor | Alarm | |
| E157 | Abnormal operation: APS Hose | Manual | |
| Central Heating Circulation | E205 | Heating supply thermistor open or short circuit | Auto |
| Water Supply | E302 | Low water pressure | Manual |
| E352 | High water pressure | Manual | |
| E353 | Abnormal operation: Water pressure sensor | Auto | |
| DHW Circulation | E407 | DHW Outlet thermistor Open or Short Circuit | Alarm |
| E421 | DHW Inlet thermistor Open or Short Circuit | Alarm | |
| E441 | DHW Outlet thermistor Open or Short Circuit | Alarm | |
| E445 | Abnormal operation: Mixing valve | Alarm | |
| E480 | DHW Tank thermistor Open or Short Circuit | Alarm | |
| Controller (PCB) | E515 | Abnormal operation: Relay feedback (PCB) | Manual |
| E517 | Abnormal operation: DIP switch setting (PCB) | Manual | |
| E594 | Abnormal operation: EEPROM (PCB) | Alarm/Manual | |
| Controller (MCU) | E615 | Abnormal operation: Input and memory (MCU) Manual | |
| Installation | E740 | Abnormal operation: Outdoor temperature sensor | Auto |
| E782 | Abnormal operation: Main panel communication | Auto | |
| E783 | Abnormal operation: OpenTherm remote control | Auto | |
| E787 | Abnormal operation: Reset device | Manual/Power Reset | |
To reset the boiler, Press the Back button on the front panel. If the error code is not cleared by resetting the boiler functioning or if it occurs repeatedly, call us on 02890 451010, indicating the number of the error code appearing on the front panel.