Navien NHB-110 Service Manual

4 NHB Service Manual
Version 1.0
7. Components Diagram and Part List 133
7.1 Case Assembly 133
7.2 Heat Exchanger and Waterway Assembly
135
7.3 Combustion Parts Assembly
138
8. Inspection and Maintenance Schedule 141
8.1 Annual Servicing 141
8.2 Maintenance Report
141
8.3 Maintenance Schedules
141
8.4 Inspection Report
141
5.2.15 278Error 112
5.2.16 279Error 113
5.2.17 291Error 114
5.2.18 302Error 115
5.2.19 352Error 116
5.2.20 353Error 117
5.2.21 515Error 118
5.2.22 517Error 119
5.2.23 594Error 119
5.2.24 615Error 120
5.2.25 740Error 120
5.2.26 777Error 121
5.2.27 782Error 122
5.2.28 784Error 122
5.3 Troubleshooting guide by symptom
123
5.3.1 Noise 123
5.3.2 Water Temperature Issue 124
5.3.3 Circuit breaker operation 125
6. Replacement of Parts 126
6.1 Replacement Procedure 126
6.2 Components Replacement Instructions
126
6.2.1 PCB 126
6.2.2 Fuse 127
6.2.3 Fan (Combustion Air) 127
6.2.4 Flame Rod 129
6.2.5 Ignition Transformer 129
6.2.6 APS 130
6.2.7 Main Gas Valve 130
6.2.8 Condensate Trap 132
6.2.9 Water Pressure Sensor 132

Navien NHB-110 Specifications

General

Category	Boiler
Brand	Navien
Model	NHB-110
Maximum Input	110, 000 BTU/h
Efficiency	95% AFUE
Weight	75 lbs
Vent Type	Direct Vent
Fuel Type	Natural Gas or Propane
Heat Exchanger Material	Stainless Steel
Water Connection Size	3/4 inch
Gas Connection Size	3/4 inch
Vent Material	PVC, CPVC, Polypropylene
Vent Size	2 inch