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NPN-180E premium features and benefits
Exclusive NaviTech™ stainless steel heat exchanger. The NPN series is the first non condensing tankless water heater with a stainless steel heat exchanger to deliver unmatched durability and performance.
NPN - Exterior 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.
NPN-180E 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
- 204524355 (Natural gas)
204524356 (Propane)
Efficiency Ratings*
- Uniform Energy Factor(UEF)
- 0.81
- MAX GPM(35°F Rise)
- 8.5
*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 | NPN-180E |
|---|---|
| 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 | NPN-180E |
|---|---|
| DHW | 10,700 - 180,000 BTU/h (3.14 - 52.74 kWh) |
| Item | NPN-180E | |
|---|---|---|
| Heat Capacity (input) | Domestic hot water | 10,700 - 180,000 BTU/h (3.14 - 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 | 4.6 GPM (17.4 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) | |
| Boiler weight | 60 lbs (27.2 kg) | |
| Installation location | Outdoor wall-hung | |
| Venting type | N/A | |
| Ignition | Electronic ignition | |
| DHW water pressure | 15-150 PSI (1.05-10.55 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) | 2.4 " WC to 0.53 " WC (0.59 kPa to 0.13 kPa) | |
| Propane gas manifold pressure (min-max) | 5.4 " WC to 1.3 " WC (1.3 kPa to 0.32 kPa) | |
| Minimum flow rate | 0.5 GPM (1.9 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 | 88 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, ignition operation detector, water temperature high limit switch, power surge fuse | |
Navien reserves the right to change specifications at any time without prior notice.
Applicable Warranty Periods
| Product | Labor | Parts | Heat Exchanger | |
|---|---|---|---|---|
NPN (Residential) | Standard or Controlled Recirculation2 | 1 Year | 5 Years | 15 Years |
Uncontrolled Recirculation3 | 1 Year | 3 Years | 5 Years | |
NPN (Commercial or Combi1) | Standard or Controlled Recirculation2 | 1 Year | 5 Years | 5 Years |
Uncontrolled Recirculation3 | 1 Year | 3 Years | 3 Years | |
NPN (Residential)
Standard or Controlled Recirculation2
NPN (Residential)
Standard or Controlled Recirculation2
Labor - 1 Year
Parts - 5 Years
Heat Exchanger - 15 Years
Uncontrolled Recirculation3
Uncontrolled Recirculation3
Labor - 1 Year
Parts - 3 Years
Heat Exchanger - 5 Years
NPN (Commercial or Combi1)
Standard or Controlled Recirculation2
NPN (Commercial or Combi1)
Standard or Controlled Recirculation2
Labor - 1 Year
Parts - 5 Years
Heat Exchanger - 5 Years
Uncontrolled Recirculation3
Uncontrolled Recirculation3
Labor - 1 Year
Parts - 3 Years
Heat Exchanger - 3 Years
1Combi refers to a combination potable water and space heating application. Water heaters cannot be used in space heating only applications.
2Controlled-Recirculation: Recirculation the water heater is controlled by either the water heater or an external aquastat.
3Uncontrolled-Recirculation: External pumps configured to circulate continuously through the water heater are subject to the uncontrolled recirculation warranty terms. An aquastat is the minimum pump control requirement for DHW or storage tank recirculation in order to maintain the full controlled warranty.
NPN‑E Videos
NPN-199E Featured Reviews
NPN-180E FAQs
Can I use ½” gas pipe with the NPE-2 condensing gas tankless water heater?
½” gas pipe can be used when installing a NPE-2 condensing gas tankless water heater as long as it is sized appropriately.
Pipe size, length of gas pipe, and pressure drop are all factors that affect gas delivery.
Please refer to the National Fuel Gas Code gas pipe sizing table to ensure you have sufficient gas supply for the unit.
Does the NPE-2 condensing tankless gas water heater have to be the first appliance off the gas meter?
No, it is not required that the NPE-2 condensing tankless gas water heater be the first appliance off the gas meter.
It can be installed using the existing infrastructure and can go in place of a traditional tank water heater so long as the gas line is sized appropriately and can deliver sufficient gas supply to the unit.
What type of venting can I use for the NPE-2 condensing tankless gas water heater?
The NPE-2 is approved to be vented with 2”vent material (maximum length of 75 feet, maximum of 6 elbows, and reduce 8 linear feet per 90° elbow). 3” vent material can also be used (maximum length of 150’, maximum of 8 elbows, and reduce 5 linear feet per 90° elbow).
Approved vent materials are PVC Schedule 40, CPVC Schedule 80, Approved Polypropylene, and stainless steel.
Can I use PVC with the NPE condensing tankless gas water heater?
Yes, with the NPE condensing tankless gas water heater you can use PVC Schedule 40, which allows for zero inch clearance to combustibles.
Does the NPE-2 condensing tankless gas water heater include a remote?
Yes, the NPE-2 has built in display and control allowing for simple and easy operation.
What is ComfortFlow technology?
Navien’s patented ComfortFlow® system is the first to include a buffer tank, recirculation pump and fine-tuned controls into a tankless water heater, resolving the cold-water sandwich effect* and issues of minimal flow rates commonly found in other tankless water heaters.
* The “cold-water sandwich effect” is the undesired introduction of cold water into the hot water supply line on occasions of frequent on/off operations. (Measure Guideline : Transitioning to a Tankless Water heater, DOE, Sept.2012).
Can the NPE-2 be mounted outdoors?
Yes, the NPE-2 can be mounted outdoors using the Navien Outdoor Vent Kit.
It is recommended the unit only be mounted outdoors in mild climates.
Please follow proper instruction procedures outlines in installation manual.
Is the NPE-2 gas field convertible?
Yes, the NPE-2 is gas field convertible.
The default gas type for the unit will be Natural Gas (NG). To convert the unit for LP use, please use gas conversion kit supplied with unit.
This should only be performed by a qualified service agency in accordance with Navien America’s instructions.
Is there commercial model available for the NPE-2 series?
The NPE-2 is approved for use in residential, commercial, and heating (combination only) applications.
If used in commercial or heating application, the warranty will be adjusted to 8 years on the heat exchanger, 5 years on any other parts, and 1 year labor.
What are Navien Technical Support (800-519-8794) hours of operation?
Monday - Friday
Pacific - 4am-8pm
Mountain - 5am-9pm
Central - 6am-10pm
Eastern - 7am-11pm
Saturday - Sunday - Holidays
Pacific - 5am-5pm
Mountain - 6am-6pm
Central - 7am-7pm
Eastern - 8am-10pm
Where are your offices located in the U.S. and Canada?
Navien Inc. (Headquarters)
20 Goodyear
Irvine, California 92618
Phone: 800-519-8794, 949-420-0430
Navien America Inc. (Branch Office)
325 Route 70 East
Cherry Hill, New Jersey 08034
Phone: 800-519-8794 Fax: 856-354-5099
Navien America Inc. (Branch Office)
346 Millway Ave. Unit 7
Vaughan, ON L4K 3W1
Phone: 800-519-8794 Fax: 905-532-9976
Where do I locate the Serial Number of my unit?
Please see the following attachment on where you can locate your serial number.
What is the warranty on Navien products?
Residential
Details about our residential warranty for Navien’s NPE series tankless water heater, NCB series combi-boiler and NHB series condensing boiler can be found here.
Commercial
Details about our commercial warranty for Navien’s NPE series tankless water heater and NHB series condensing boiler can be found here.
What are the terms of Navien's labor warranty?
The applicable period for this labor allowance for all water heater models is One (1) year from the effective date.
The payment and amount of any payment are subject to approval at Navien’s sole discretion.
The labor allowance will be paid based on Navien’s schedule of labor allowances.
I am a homeowner and have a problem with my unit. If I call technical support, can they walk me through troubleshooting my unit?
Because our product involves water, electricity, and gas, there is only a limited amount of troubleshooting that can be done with a homeowner/end-user.
We recommend contacting your original installer or a Navien Service Specialist (NSS) to troubleshoot the unit.
NOTE: Charges will apply for service calls outside of 1 year labor period and/or non-warranty issues. Please see terms of our labor warranty.
Does Navien have Field Technicians available to service my unit?
Because our product involves water, electricity, and gas, there is only a limited amount of troubleshooting that can be done with a homeowner/end-user. We recommend contacting your original installer or a Navien Service Specialist (NSS) to troubleshoot the unit. NOTE: Charges will apply for service calls outside of 1 year labor period and/or non-warranty issues. Please see terms of our labor warranty.
I have no error codes on my remote, yet my unit will not produce hot water. What should I do?
The issue is most likely the flow sensor inside the unit is not spinning properly.
We recommend opening and closing the pressure relief valve (should be located near the outlet of the unit). Depending on amount of debris affecting the flow sensor, this may help temporary. We recommend contacted your original installer or an NSS to service the sensor.
I think there is a part that needs to replaced, how do I get a new part shipped out to me?
If you feel like there is an issue with your unit, please have someone contact Navien Technical Support while in front of the unit with your Serial Number ready. We recommend that a license contractor, original installer, or NSS contact is the person who calls us, so we may do in depth troubleshooting to determine if there is a part failure.
Navien Technical Support will be unable to send out parts without registration of product (Serial Number, Date of Installation, Homeowner Information, and Installer Information).