Navien NFC-175, Service Manual

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4 NFC Service Manual
Version 1.0
7. Components Diagram and Part List 126
7.1 Case Assembly 126
7.2 Heat Exchanger and Waterway Assembly 128
7.3 Combustion Parts Assembly 130
8. Inspection and Maintenance Schedule 132
8.1 Annual Servicing 132
8.2 Maintenance Report 132
8.3 Maintenance Schedules 132
8.4 Inspection Report 132
5.2.11 110Error 93
5.2.12 205Error 95
5.2.13 218Error 97
5.2.14 278Error 99
5.2.15 279Error 100
5.2.16 291Error 101
5.2.17 302Error 102
5.2.18 351Error 103
5.2.19 352Error 104
5.2.20 353Error 105
5.2.21 407Error 106
5.2.22 421Error 107
5.2.23 434Error 108
5.2.24 439Error 109
5.2.25 441Error 110
5.2.26 445Error 111
5.2.27 515Error 112
5.2.28 517Error 113
5.2.29 594Error 113
5.2.30 615Error 114
5.2.31 740Error 114
5.2.32 777Error 115
5.2.33 782Error 116
5.2.34 784Error 116
5.2.35 777 & 031Error 117
5.3 Troubleshooting guide by symptom 119
5.3.1 Noise 119
5.3.2 Water Temperature Issue 120
6. Replacement of Parts 121
6.1 Replacement Procedure 121
6.2 Components Replacement Instructions 121
6.2.1 PCB 121
6.2.2 Fuse 122
6.2.3 Fan (Combustion Air) 122
6.2.4 Flame Rod 123
6.2.5 Ignition Transformer 123
6.2.6 APS 124
6.2.7 Main Gas Valve 125
6.2.8 Water Pressure Sensor 125