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NHW-180AI premium features and benefits
ComfortFlow® built-in recirculation system
The patented ComfortFlow® system is the first to include a buffer tank, recirculation pump and fine-tuned controls into a tankless water heater.
NHW-A Built-in control panel
Allows you to adjust water temperature, operation status and troubleshooting.
Built-in Air Pressure Sensor (APS)
Monitors vent system for blockage, automatically compensates for range of vent lengths, helps maintain proper air/gas ratio during operation, and ensures consistent hot water output during changing conditions.
Includes advanced safety features Such as the Vent Installation Detector (VID)
Built-in Water Adjustment Valve (WAV) & Mixing Valve
Control flow to maintain setpoint and stabilize water temperature during flow changes.
Exclusive NaviTech™ stainless steel heat exchanger
The NWH700 series non-condensing tankless water heaters feature a stainless steel heat exchanger to deliver unmatched durability and performance.
Patented NaviTech™ stainless steel gas 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.
NHW-180AI QuickFacts
17.3" W x 26.5" H x 10.3" D (43.9cm W x 67.3cm H x 26.2cm D)
Product approvals
- CSA
- Yes
- NSF(Standard 5)
- Yes
- Low Lead(<0.25%)
- Yes
- Ultra low NOx
- Yes
- AHRI Number
- 212617042 (Natural gas)
212617048 (Propane)
Efficiency Ratings*
- Uniform Energy Factor(UEF)
- 0.81
- MAX GPM(67°F Rise)
- 4.5 GPM (17 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-180AI |
|---|---|
| 30 °F (16.7 °C) rate | 10 GPM (37.9 l/m) |
| 35 °F (19.4 °C) rate | 8.5 GPM (32.2 l/m) |
| 40 °F (22.2 °C) rate | 7.5 GPM (28.4 l/m) |
| 45 °F (25 °C) rate | 6.6 GPM (25 l/m) |
| 50 °F (27.8 °C) rate | 6 GPM (22.7 l/m) |
| 55 °F (30.6 °C) rate | 5.4 GPM (20.4 l/m) |
| 60 °F (33.3 °C) rate | 5 GPM (18.9 l/m) |
| 65 °F (36.1 °C) rate | 4.6 GPM (17.4 l/m) |
| 70 °F (38.9 °C) rate | 4.3 GPM (16.3 l/m) |
| 75 °F (41.7 °C) rate | 4 GPM (15.1 l/m) |
| 80 °F (44.4 °C) rate | 3.7 GPM (14 l/m) |
| 85 °F (47.2 °C) rate | 3.5 GPM (13.2 l/m) |
| 90 °F (50 °C) rate | 3.3 GPM (12.5 l/m) |
| 100 °F (55.6 °C) rate | 3 GPM (11.4 l/m) |
| Model | NHW-180AI |
|---|---|
| DHW | 10,700 - 180,000 BTU/h (3.135 - 52.74 kWh) |
| Item | NHW-180AI | |
|---|---|---|
| Heat Capacity (input) | Domestic hot water | 10,700 - 180,000 BTU/h (3.135 - 52.74 kWh) |
| Efficiency ratings | Efficiency rating for NG & LP (UEF) | 0.81 |
| Flow rate (DHW) | 35°F temp rise | 8.5 GPM (32.2 l/m) |
| 45°F temp rise | 6.6 GPM (25 l/m) | |
| 67°F temp rise | 4.5 GPM (17 l/m) | |
| Dimensions | 17.3" W x 26.5" H x 10.3" D (43.9cm W x 67.3cm H x 26.2cm D) | |
| Weight | 65 lbs (29.5 kg) | |
| Installation location | Indoor wall-hung | |
| 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) | 2.3 " WC to 0.7 " WC (0.57 kPa to 0.17 kPa) | |
| Propane gas manifold pressure (min-max) | 4.5 " WC to 1.3 " WC (1.1 kPa to 0.32 kPa) | |
| Minimum flow rate | 0.4 GPM (1.514 l/m), < 0.01 GPM (0.04 l/m) with ComfortFlow* | |
| Connection sizes | Cold water inlet | 3/4" NPT |
| Hot water outlet size | 3/4" NPT | |
| Gas inlet | 3/4" NPT | |
| Power supply | Main supply | 120V AC, 60 Hz |
| Normal | 100 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, VID (vent installation detector), ignition operation detector, water temperature high limit switch, power surge fuse | |
* Available for NHW-A Models configured in an optional ComfortFlow® recirculation mode.
Energy consumption will increase when the system is configured for recirculation.
Navien reserves the right to change specifications at any time without prior notice.
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