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43.2cm W x 61.0cm H x 30.5cm D (17.0" W x 24.0" H x 12.0" D)
Product approvals
- CSA
- Yes
- SCAQMD 1146.2(NOx, <20ppm)
- Yes
- ASME Certified
- Yes "H" Stamp
- AHRI number
- 7501495
- Energy star certified
- Yes
- ance_nom_certified
- Yes
Space Heating Ratings
- AFUE, %
- 95.0
- Heating Capacity
- 51,000 BTU/h
| Model | NHB-55 |
|---|---|
| Range | 8,000 - 55,000 BTU/h |
| TDR | 7:1 |
Navien Condensing Boiler Space Heating Ratings | ||
|---|---|---|
| Model1 | NHB-55 | |
| Heating Input | Min | 8,000 BTU/h |
| Max | 55,000 BTU/h | |
| Heating Capacity2 | 51,000 BTU/h | |
| Net AHRI Rating, Water3 | 44,000 BTU/h | |
| AFUE2, % | 95 | |
1 Ratings are the same for Natural Gas models converted to Propane use.
2 Based on U.S. Department of Energy (DOE) test procedures.
3 The NET AHRI Water Ratings shown are based on a piping and pickup allowance of 1.15. Consult Navien before selecting a boiler for installations having unusual piping and pickup requirements, such as intermittent system operation, extensive piping systems, etc.
| Item | NHB-55 | |
|---|---|---|
| Dimensions | 43.2cm W x 61.0cm H x 30.5cm D (17.0" W x 24.0" H x 12.0" D) | |
| Boiler weight | 33.1 kg (73 lbs) | |
| Installation location | Indoor wall-hung | |
| Venting type | Forced draft direct vent | |
| Ignition | Electronic ignition | |
| Natural gas supply pressure (from source) | 3.5 " WC to 10.5 " WC | |
| Propane gas supply pressure (from source) | 8 " WC to 13 " WC | |
| Natural gas manifold pressure | -0.03 " WC | |
| Propage gas manifold pressure | -0.03 " WC | |
| Connection sizes | Gas inlet | 3/4" NPT (hembra) |
| Power Supply | Main supply | 120V AC, 60Hz |
| Maximum power consumption | Less than 10A | |
| Materials | Casing | Cold rolled carbon steel |
| Heat exchangers | Primary and secondary heat exchangers: stainless steel | |
| Venting | Exhaust | 2" or 3" PVC, CPVC, approved polypropylene (see installation manual for more details) 2" or 3" special gas vent type BH (Class III, A/B/C) |
| Intake | 2" or 3" PVC, CPVC, polypropylene 2" or 3" special gas vent type BH (Class III, A/B/C) | |
| Vent clearances | 0" to combustibles | |
| Safety Devices | Flame rod, APS, gas valve operation detector, ignition operation detector, water temperature high limit switch, exhaust temperature high limit sensor | |
Navien reserves the right to change specifications at any time without prior notice.
Coverage Table for Labor and Parts Only
| Product | Labor | Parts | Heat Exchanger |
|---|---|---|---|
Residential* | 1 Year | 5 Years | See table below |
Commercial | 1 Year | 3 Years | See table below |
Residential*
Residential*
Labor - 1 Year
Parts - 5 Years
Heat Exchanger - See table below
Commercial
Commercial
Labor - 1 Year
Parts - 3 Years
Heat Exchanger - See table below
* Applies only to single family, residential locations.