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NHW-199SU premium features and benefits
Exclusive stainless steel heat exchanger. The NHW-S series is the first non condensing tankless water heater with a stainless steel heat exchanger to deliver unmatched durability and performance.
NPN - Universal integrated control panel allows you to adjust water temperature, operation status and troubleshooting.
Built-in Air Pressure Sensor (APS) monitors the vent system for blockage, automatically compensates for the range of vent lengths, helps maintain proper air/gas ratio during operation, and ensures consistent Domestic Hot Water output during changing conditions.
Patented NaviTech™ stainless steel burner. Designed and manufactured by Navien to burn gas at higher efficiency than other system on the market.
Recirculation control built into circuit board. Ensures proper system setup, and reduces the need for additional components, saving installation time and cost.
Built-in Water Adjustment Valve (WAV) and Mixing Valve control flow to maintain setpoint, and stabilize water temperature during flow changes
NHW-199SU QuickFacts
14.0" W x 23.0" H x 9.3" D (35.6cm W x 58.4cm H x 23.6cm D)
Product approvals
- CSA
- Yes
- NSF(Standard 5)
- Yes
- Low Lead(<0.25%)
- Yes
- Ultra low NOx
- Yes
- AHRI Number
- 204524349 (Natural gas)
204524350 (Propane)
Efficiency Ratings*
- Uniform Energy Factor(UEF)
- 0.81
- MAX GPM(67°F Rise)
- 5.4 GPM (20.4 l/m)
*Based on U.S. Department of Energy (DOE) test procedures.**Based on a national average natural gas cost of $1.09/therm, propane cost of $2.41/gallon.
| Temp Rise | NHW-199SU |
|---|---|
| 30 °F (16.7 °C) rate | 11.1 GPM (42 l/m) |
| 35 °F (19.4 °C) rate | 9.5 GPM (36 l/m) |
| 40 °F (22.2 °C) rate | 8.3 GPM (31.4 l/m) |
| 45 °F (25 °C) rate | 7.4 GPM (28 l/m) |
| 50 °F (27.8 °C) rate | 6.6 GPM (25 l/m) |
| 55 °F (30.6 °C) rate | 6 GPM (22.7 l/m) |
| 60 °F (33.3 °C) rate | 5.5 GPM (20.8 l/m) |
| 65 °F (36.1 °C) rate | 5.1 GPM (19.3 l/m) |
| 70 °F (38.9 °C) rate | 4.7 GPM (17.8 l/m) |
| 75 °F (41.7 °C) rate | 4.4 GPM (16.7 l/m) |
| 80 °F (44.4 °C) rate | 4.1 GPM (15.5 l/m) |
| 85 °F (47.2 °C) rate | 3.9 GPM (14.8 l/m) |
| 90 °F (50 °C) rate | 3.7 GPM (14 l/m) |
| 100 °F (55.6 °C) rate | 3.3 GPM (12.5 l/m) |
| Model | NHW-199SU |
|---|---|
| DHW | 10,700 - 199,900 BTU/h (3.135 - 58.571 kWh) |
| Item | NHW-199SU | |
|---|---|---|
| Heat Capacity (input) | Domestic hot water | 10,700 - 199,900 BTU/h (3.135 - 58.571 kWh) |
| Efficiency ratings | Efficiency rating for NG & LP (UEF) | 0.81 |
| Flow rate (DHW) | 35°F temp rise | 9.5 GPM (36 l/m) |
| 45°F temp rise | 7.4 GPM (28 l/m) | |
| 67°F temp rise | 5.4 GPM (20.4 l/m) | |
| Dimensions | 14.0" W x 23.0" H x 9.3" D (35.6cm W x 58.4cm H x 23.6cm D) | |
| Weight | 65 lbs (29.5 kg) | |
| Installation location | Indoor or outdoor wall-hung (vent cap kit required for outdoor) | |
| Venting type | Forced draft direct vent (indoor only) | |
| Ignition | Electronic ignition | |
| DHW water pressure | 15-150 PSI (1.055-10.545 kg/cm2) | |
| Natural gas supply pressure (from source) | 3.5 " WC to 10.5 " WC (0.87 kPa to 2.61 kPa) | |
| Propane gas supply pressure (from source) | 8 " WC to 13 " WC (1.99 kPa to 3.23 kPa) | |
| Natural gas manifold pressure (min-max) | 2.8 " WC to 0.7 " WC (0.7 kPa to 0.17 kPa) | |
| Propane gas manifold pressure (min-max) | 5.4 " WC to 1.3 " WC (1.3 kPa to 0.32 kPa) | |
| Minimum flow rate | 0.26 GPM (0.984 l/m) | |
| Connection sizes | Cold water inlet | 3/4 |
| Hot water outlet size | 3/4 | |
| Gas inlet | 3/4 | |
| Power supply | Main supply | 120V AC, 60 Hz |
| Normal | 115 W | |
| Standby | 4 W | |
| Anti-frost | 114 W | |
| External pump | < 150 W, 1.5 A W | |
| Fuse | 5.0 A | |
| Materials | Casing | Cold rolled carbon steel |
| Heat exchangers | Stainless steel | |
| Safety Devices | Flame Rod, APS, Vent Installation Detector, Ignition Operation Detector, Water Temperature High Limit Switch, Power Surge Fuse | |
Navien reserves the right to change specifications at any time without prior notice.
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