Table Of Contents - Navien NR Series Service Manual

Table of Contents

Table Of Contents2
Specifications4
Exterior View5
Interior View And List Of Main Components7
Schematic And Water Flow Diagram11
Operation15
Firing Sequence15
Shut-Down Sequence15
Standby Mode15
Replaceable Major Components16
Primary Heat Exchanger18
Secondary (Condensing) Heat Exchanger19
Fan20
Pump21
Gas Valve22
Water Adjustment Valve23
Buffer Tank24
Gas Pressure Sensor (Gps)25
Air Pressure Sensor (Aps)26
Flow Sensor27
High Limit Switch Or Exhaust Limit Switch28
Thermostat29
Ignition Transformer30
Transformer31
Thermal Fuse32
Burner33
Manifold34
Pcb Board35
Bypass Mixing Valve36
Igniter37
Wiring Diagram38
Pcb Board Check Points For Diagnosis42
Operational Flow Chart45
Abbreviation And Definition45
Error Code And Troubleshooting50
Power Supply Troubleshooting52
Boiling Inside Heat Exchanger54
Ignition Failure55
False Flame Deflection57
Outlet Thermostat Open58
Outlet Thermostat Short58
Fan Motor Rpm Error59
Air Pressure Sensor Error60
Flame Loss61
Cold Water Inlet Thermostat Open/Short62
Water High Limit/Overheat Cut-Off Fuse Error63
Exhaust High Limit Error63
Abnormal Air Pressure Sensor64
Abnormal Water Adjustment Valve65
Abnormal Gas Pressure Sensor66
Leak Detect67
Abnormal Circulation Pump67
Abnormal The Water Flow Sensor68
Abnormal Lpg Gas Pressure68
Communication Error With Pcb Board69
Communication Failure69
Outlet Thermistor 2 Open/Short69
Cascade Connection Abnormal70
Thermostats Connection Abnormal70
Anbormal Mixing Valve71
Disassemble, Replace And Repair72
Fan (Combustion Air Blow)73
Fuse74
Igniter Removal75
Ignition Transformer Removal76
Air Pressure Sensor (Aps) Removal77
Pcb Board Removal78
Gas Pressure Sensor (Gps) (Disassembly And Assembly)83
Condensation Trap84
Buffer Tank (Disassembly And Assembly)85
Pump (Disassembly And Assembly)86
Transformer (Disassembly And Assembly)88
3-Way Valve89
Water Adjustment Valve (Disassembly And Assembly)90
Flow Sensor (Disassembly And Assembly)91
2-Way Valve92
Bypass Mixing Valve (Disassembly And Assembly)93
Exploded Views And Parts Lists94
Measuring Gas Pressure Setting106
Procedure For Measuring The Inlet Gas Pressure106
Measuring The Gas-Air Pressure Differential Pressure Setting107
Standard Setting Chart Of The Gas-Air Pressure108