Error Code Classification - Navien NHB-055 Service Manual

5.2 Error code classification

Error Code Sub Code
1
E001
2
E003 0
E004 0
E012 0
E016 0
Version 1.0
Function
Overheating of Heat exchanger
Ignition failure
False flame detection
Flame loss
Overheating of heat exchanger
Self-diagnostic / Action
1. Clean the strainer.
2. Check the pump for proper voltage from
PCB(120VAC)
3. Check for proper flow rate and
circulation(external) through the heating line
4. Check the heat exchanger ; flush with a cleaning
solution
1. Check to see if the main gas supply valve is open.
2. Verify that gas pressure is within operating
range.
3. Check gas system and orifice.
4. Check Dual Venturi for proper operation.
5. Check for proper dipswitch settings (see
page 21)
6. Tighten the ground connection screws on heat
exchanger.
1. Ensure ground wire is connected.
2. Check the igniter for spark.
1. Check the main gas line (Is the valve open?)
2. Verify gas pressure is within operating range.
3. Check gas meter for proper BTU capacity.
4. Check flame rod and verify [K] value in
DIAGNOSTIC.
5. Check intake air filter.
6. Check ground wire.
7. Check power supply.
8. Tighten the ground connection screws on heat
exchanger.
9. Adjust anti-short cycle time.
1. Turn OFF the system for at least 30 minutes then
restart.
2. Clean the inlet water filter.
3. Check for proper dipswitch settings (see
page 19-20) and PCB.
4. Check the heat exchanger; a flush may be
necessary.
5. Check if Air Venting is fully made in the boiler
and system piping and carry out Air Venting.
NHB Service Manual 79