Secondary Heat Exchanger - Navien NCB-24LSWE Service Manual

4.9.12 Secondary Heat Exchanger

Item
Function
Fault
Symptoms
Error codes
Diagnostics
Version 1.0
1. Secondary component used in the boiler for heat transfer.
2. There are multiple paths of water pipes on the heat exchanger as well as inside the
combustion chamber which minimises heat loss.
1. Water and/or exhaust gas leaks.
2. Scale deposits in the heat exchanger can cause water in the boiler to bubble.
1. Exhaust gas leaks.
2. Overheating of water causes bubbling noises.
E016, E030, E047
1. Visual inspection: Check for surface cracks on the heat exchanger.
2. Audible inspection: Listen for bubbling noises from inside the boiler.
Description
NCB Service Manual 71