Error Codes - Navien LCB700-21RS Installation & Operation Manual

11.6 Error 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
Combustion
Air Circulation
Central Heating
Circulation
Water Supply
DHW Circulation
Controller (PCB)
Controller (MCU)
Installation
If the error code is not cleared by resetting the boiler functioning (see "11.3.3 Resetting the Boiler") or if it occurs repeatedly, call the
nearest official Technical Assistance Service (TAS), indicating the number of the error code appearing on the front panel.
E001 Overheating of heat exchanger
E003 Ignition failure
E004 False flame detection
E012 Flame loss
E016 Heat exchanger overheat
E030 Abnormal exhaust temperature
E031 Burner overheat
E046 Abnormal operation: Heat exchanger overheating sensor
E047 Abnormal operation: Exhaust thermostat
E056 Abnormal operation: Oil pump
E109 Abnormal operation: Fan
E110 Exhaust blockage (Condensate blockage)
E127 Abnormal operation: APS
E144 Abnormal operation: Burner temperature sensor
E157 Abnormal operation: APS Hose
E205 Heating supply thermistor open or short circuit
E302 Low water pressure
E352 High water pressure
E353 Abnormal operation: Water pressure sensor
E407 DHW Outlet thermistor Open or Short Circuit
E421 DHW Inlet thermistor Open or Short Circuit
E441 DHW Outlet thermistor Open or Short Circuit
E445 Abnormal operation: Mixing valve
E480 DHW Tank thermistor Open or Short Circuit
E515 Abnormal operation: Relay feedback (PCB)
E517 Abnormal operation: DIP switch setting (PCB)
E594 Abnormal operation: EEPROM (PCB)
E615 Abnormal operation: Input and memory (MCU)
E740 Abnormal operation: Outdoor temperature sensor
E782 Abnormal operation: Main panel communication
E783 Abnormal operation: OpenTherm remote control
E787 Abnormal operation: Reset device
Description Reset
Manual
Manual
Auto
Manual
Manual
Manual
Manual
Auto
Manual/Auto
Manual
Manual
Manual
Auto (Manual)
Alarm
Manual
Auto
Manual
Manual
Auto
Alarm
Alarm
Alarm
Alarm
Alarm
Manual
Manual
Alarm/Manual
Manual
Auto
Auto
Auto
Manual/Power Reset
Operating the Boiler 67