Error Code List And Actions - Navien NCB-700-2S+/42K Service Manual

5.2 Error Code List and Actions

Error Code Sub Code
E001 0
E003 0
E004 0
E012 0
E016 0
E030 0
E031 2
E046 2
1
E047
2
1
2
E060
3
62 Troubleshooting
Function
Overheating of heat exchanger
Ignition failure
False flame detection
Flame loss
Heat exchanger overheat
Abnormal exhaust temperature.
Overheating of burner
Abnormal operation: Heat
exchanger overheating sensor
Exhaust thermistor open error
Exhaust thermistor short error
Dual venturi limit switch error (ON)
Dual venturi limit switch error
(Closed OFF)
Dual venturi limit switch error
(Open ON)
Diagnosis/Actions
1. Clean the strainer.
2. Check voltage via PCB at the pump.
3. (AC 230 V)
4. Check that the flow rate is correct.
5. Check if water is circulating in the heating lines.
6. Check the heat exchanger and flush it with cleaning solution if
necessary.
1. Check the main gas supply
2. Check if the manual gas valve is open.
3. Check if the igniter is sparking.
4. Tighten the ground terminals on the heat exchanger.
1. Ensure that the ground wire is connected.
2. Check if the igniter is sparking.
1. Check if the main gas valve is open and verify the incoming gas
pressure.
2. Check the intake air filter.
3. Check the ground wire.
4. Check the power supply.
5. Tighten the ground terminals on the heat exchanger.
6. Adjust the anti-short cycle time.
1. Turn OFF the boiler, wait at least 30 min, and then restart the boiler.
2. Clean the inlet water filter and strainer.
3. Check the high limit switch and PCB.
4. Check the 3-way valve.
5. Check the heat exchanger and flush it if required.
1. Turn OFF the boiler, wait at least 30 min, and then restart the boiler.
2. Clean the strainer.
3. Check the heat exchanger and flush it if required.
1. Turn off the boiler.
2. Check if all the valves on the distribution manifold are closed.
3. Check if the burner overheat prevention is disconnected.
Check the heat exchanger thermistor connection.
Check the exhaust thermistor connection.
Check the dual venturi connection.