Understanding Error Codes - Navien NPE-210A Operation Manual

5.2 Understanding 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.
Error Code Reason
E003 Ignition failure
E004 False flame detection
E012 Flame loss
E016 Overheating of heat exchanger
Exhaust overheating (the water heater shuts down
E030
when the flue temperature exceeds 149 °F (65 °C)
E046 Abnormal operation: limit control
E047 Abnormal operation: exhaust thermostat
E060 Abnormal operation: dual venturi
E109 Abnormal operation: fan motor
E110 Abnormal air pressure
E407 Hot water outlet: thermistor open or short circuit
E421 Cold water inlet1: thermistor open or short circuit
E432 Cold water inlet2: thermistor open or short circuit
E434 Abnormal operation: water adjustment valve
E438 Abnormal operation: circulation pump
E439 Abnormal operation: flow sensor
E441 Hot water inlet2: thermistor open or short circuit
E445 Abnormal operation: Bypass mixing valve
E515 Abnormal operation: PCB
E517 Abnormal operation: DIP switch setting
E593 Abnormal operation: front panel key
E615 Abnormal operation: input and memory
E736 Abnormal operation: cascade communication
E740 Abnormal operation: outdoor temperature sensor
E760 Flushing/service alarm
E782 Abnormal operation: main panel communication
E785 Abnormal operation: flow switch/sensor
If any of these remedies do not resolve the problem, contact Technical Support at 1-800-519-8794.
16 Troubleshooting
Self-diagnostic / Action
Ensure that the main gas supply valve is open.
Ensure that the electrical cord is properly grounded.
Clean the intake air filter. See page 13.
Ensure that the electrical cord is properly grounded.
Turn off the system for at least 30 minutes, and then restart it.
Clean the cold water inlet filter. See page 12.
Flush the heat exchanger. See page 11.
Turn off the system for at least 30 minutes, and then restart it.
Clean the cold water inlet filter. See page 12.
Flush the heat exchanger. See page 11.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Clean the intake air filter. See page 13.
Ensure that the exhaust pipe is free of obstructions.
Clean the intake air filter. See page 13.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
External: Ensure that all water supply and return lines are open.
Internal: Check the direction of the 2-way valve.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Ensure that the electrical cord is properly grounded.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.
Contact the installer to perform routine service.
Contact Technical Support at 1-800-519-8794.
Contact Technical Support at 1-800-519-8794.