Hot Water List

Navien NPE-180A2

Navien NPE-180A2 is in the DOE listing as of Oct 26, 2026 and is in the ENERGY STAR list as of Oct 26, 2026.

It has a certified UEF of 0.95 and a certified flow of 4.3 gal/min at a 67°F rise.

Its advertised flow of 4.3 gal/min at a 67°F rise from Navien matches the certified 4.3 gal/min at a 67°F rise (Read Oct 5, 2026).

  • Gas tankless water heater
  • 1 listed model

Certified and advertised figures

Flow at a 67°F rise
4.3gallons per minuteCertified
Advertised flow
4.3gallons per minuteNavien, at a 67°F rise
UEF
0.95Uniform energy factor

Flow where you live

The heater gives less flow when colder incoming water needs a bigger rise.

Cold water
Cold water must be at least 10°F colder than the hot water setting.
Flow estimate
The estimate uses the lowest certified flow among the listed models. It is about 4.1 gal/min at a 70°F rise.

Flow limits

  • The estimate excludes the flow needed to turn the heater on, heat lost in pipes, and installation.
  • Cold water from a well or long pipe run can differ from the temperature you enter.
  • Without a stated flow limit, estimates for warmer water may exceed the heater’s actual flow.

Advertised and certified figures

Navien NPE-180A2: advertised and certified
Navien NPE-180A2: advertised and certified UEF: advertised 0.95, certified 0.95. Flow: advertised 4.3 gal/min, certified 4.3 gal/min (advertised at a 67°F rise, certified at a 67°F rise). Flow: advertised 8.4 gal/min, certified 4.3 gal/min (advertised at a 35°F rise, certified at a 67°F rise). Flow: advertised 7.4 gal/min, certified 4.3 gal/min (advertised at a 40°F rise, certified at a 67°F rise). UEF Advertised 0.95 Certified 0.95 Flow · advertised at a 67°F rise, certified at a 67°F rise Advertised 4.3 gal/min Certified 4.3 gal/min Flow · advertised at a 35°F rise, certified at a 67°F rise Advertised 8.4 gal/min Certified 4.3 gal/min Flow · advertised at a 40°F rise, certified at a 67°F rise Advertised 7.4 gal/min Certified 4.3 gal/min
Navien NPE-180A2: advertised figures, where and when read
FigureAdvertisedCertifiedAdvertiserRead
UEF 0.95 0.95 Navien Read Oct 5, 2026
Flow 4.3 gal/min at a 67°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 8.4 gal/min at a 35°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 7.4 gal/min at a 40°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 6.5 gal/min at a 45°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 5.9 gal/min at a 50°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 5.3 gal/min at a 55°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 4.9 gal/min at a 60°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 4.5 gal/min at a 65°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 4.2 gal/min at a 70°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 3.9 gal/min at a 75°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 3.7 gal/min at a 80°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 3.5 gal/min at a 85°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 3.3 gal/min at a 90°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 2.9 gal/min at a 100°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 2.7 gal/min at a 110°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 2.5 gal/min at a 120°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 2.3 gal/min at a 130°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026
Flow 2.1 gal/min at a 140°F rise 4.3 gal/min at a 67°F rise Navien Read Oct 5, 2026

See how advertised flow compares across tankless models

Certified figures by listed model

Navien NPE-180A2: certified figures by listed model
Model numberUEFFlow at a 67°F rise (gal/min)Recovery efficiencyDraw pattern
NPE-180A20.954.398%High

UEF is the uniform energy factor. A dash means the model has no such figure.

ENERGY STAR certified models

Navien NPE-180A2: ENERGY STAR certified models
Model numberUEFFlow at a 67°F rise (gal/min)
NPE-180A20.954.3

It warms 4.3 gallons per minute of water from 58°F to 125°F in the test. The median gas tankless model heats 4.8 gallons per minute by 67°F. Of 487 gas tankless models, 346 have a higher flow than this one.

The single model number sold under it is ENERGY STAR certified. In tests, 95% of the energy it uses ends up as hot water (UEF 0.95). In the test, daily hot water use was set to high (its draw pattern). Among 399 gas tankless models on its draw pattern, 49 have a higher UEF. On its draw pattern, the median gas tankless UEF is 0.93. While it heats water, 98% of the energy used goes into the water (its recovery efficiency).

In 7 states, 6 rebate programs may accept it. Another 2 rebate programs may accept it if it meets their other terms.

Rebates

Programs change their terms. Check the program's own page before you buy.

Updated Oct 26, 2026 · Methodology

Not covered

  • Changes to an advertised figure after the date beside it.