Navien NFB Series, Installation & Operation Manual, Page: 3 / 232

3 Contents
Contents
1. About the Boiler 6
1.1 Included Items 6
1.2 Accessories 6
1.3 Specifications 7
1.4 Components 9
1.5 Dimensions 11
1.6 Rating Plate 12
2. Installing the Boiler 13
2.1 Removing the Wood Pallet from the boiler 13
2.2 Choosing an Installation Location 14
2.3 Mounting the Boiler to the Wall 16
3. Installing the System Piping 17
3.1 Installing a Space Heating System 17
3.2 Connecting the Condensate Drain 24
3.3 Filling the System 27
3.4 Testing the Water System 27
3.5 Examples of System Applications 28
3.6 Examples of Electrical Connections 34
4. Connecting the Gas Supply 46
4.1 Gas Pipe Sizing Tables 48
4.2 Measuring the Inlet Gas Pressure 49
5. Venting the Boiler 51
5.1 Selecting a Vent Type 52
5.2 Selecting Vent Pipe Materials 55
5.3 Measuring Vent Length 56
5.4 Terminating the Vent 56
6. Setting the DIP Switches 59
6.1 DIP Switch 1 (6 switch unit) 59
6.2 Dip Switch 2 (8 switch unit) 59
7. Connecting the Power Supply 60
8. Installing a Cascade System 61
8.1 Connecting Water Supplies 61
8.2 Connecting the Communication Cables 65
9. Installing a Common Vent System 66
9.1 About the Common Vent System 66
9.2 Navien Backflow Damper (Back-draft Damper) 71
9.3 Starting the Common Vent System 72
9.4 Connecting and Terminating the Vent Pipe 74
9.5 Setting Up the Common Vent System 75
9.6 Common Vent Termination Clearances 75
9.7 Installing a Condensate Drain 77
9.8 Exhaust Vent Termination Clearances (For Direct Vent) 78
9.9 Maintenance 79
10. Installation Checklist 80
11. Operating the Boiler 83
11.1 Turning the Boiler On or Off 83
11.2 Adjusting the Temperature 83
11.3 Accessing Basic Menu Items 85
11.4 Accessing Advanced Menu Items 89
12. Appendixes 97
12.1 Gas Conversion 97
12.2 Wiring Diagram 102
12.3 Ladder Diagram 103
12.4 Outdoor Temperature Sensor 104
12.5 Outdoor Reset Control 105
12.6 Component Assembly Diagrams and Parts Lists 106