Model specs

NWP500S065AUMB

Name: Navien NWP500S065AUMB
Brand: Navien

Navien / 61-Gallon Heat Pump Water Heater

Lower running cost than standard electric, but height, 240V, and condensate still decide fit.

Shortlist Running cost Your state Install change Full specs

UEF4.03Certified efficiency

First hour80 galHot water delivery

Footprint63" × 25"Height × depth

Running cost~$217/yrU.S. average electricity

Estimated annual savings: $734 compared to a standard standard electric tank. Based on U.S. average energy prices. See all heat pump models

NWP500S065AUMB operating cost

This unit saves roughly $734 every year compared to the standard electric tank it replaces

NWP500S065AUMB

$217/yr

Std tank (0.92 UEF)

$952/yr

~1.6year payback

At $734/yr in savings, the upfront premium pays for itself in about 1.6 years. Over 10 years: roughly $6,140 in net savings.

Your state changes the math. Annual cost ranges from ~$136/yr (ND) to ~$495/yr (HI).

U.S. avg electricity: 17.4¢/kWh (EIA, Jan 2026). The federal tax credit of up to $2,000 under IRA Section 25C expired December 31, 2025. State and utility rebates may still apply.

Your state changes the cost. Ranges from $136/yr to $495/yr depending on your state's electricity rate.

NWP500S065AUMB cost by state

Ranges from $136/yr to $495/yr depending on your state's electricity rate. U.S. average: $217/yr.

Alabama$200/yr16.1¢/kWh Alaska$318/yr25.5¢/kWh Arizona$194/yr15.6¢/kWh Arkansas$154/yr12.3¢/kWh California$377/yr30.3¢/kWh Colorado$205/yr16.4¢/kWh Connecticut$352/yr28.3¢/kWh Delaware$206/yr16.5¢/kWh District of Columbia$295/yr23.7¢/kWh Florida$198/yr15.9¢/kWh Georgia$180/yr14.5¢/kWh Hawaii$495/yr39.8¢/kWh Idaho$150/yr12.1¢/kWh Illinois$204/yr16.4¢/kWh Indiana$202/yr16.2¢/kWh Iowa$160/yr12.8¢/kWh Kansas$178/yr14.3¢/kWh Kentucky$178/yr14.3¢/kWh Louisiana$155/yr12.5¢/kWh Maine$383/yr30.7¢/kWh Maryland$257/yr20.6¢/kWh Massachusetts$388/yr31.2¢/kWh Michigan$243/yr19.5¢/kWh Minnesota$187/yr15.0¢/kWh Mississippi$177/yr14.2¢/kWh Missouri$147/yr11.8¢/kWh Montana$160/yr12.9¢/kWh Nebraska$146/yr11.8¢/kWh Nevada$174/yr14.0¢/kWh New Hampshire$328/yr26.3¢/kWh New Jersey$288/yr23.1¢/kWh New Mexico$183/yr14.7¢/kWh New York$353/yr28.4¢/kWh North Carolina$170/yr13.7¢/kWh North Dakota$136/yr10.9¢/kWh Ohio$219/yr17.6¢/kWh Oklahoma$157/yr12.6¢/kWh Oregon$183/yr14.7¢/kWh Pennsylvania$251/yr20.2¢/kWh Rhode Island$375/yr30.1¢/kWh South Carolina$192/yr15.4¢/kWh South Dakota$169/yr13.6¢/kWh Tennessee$163/yr13.1¢/kWh Texas$195/yr15.7¢/kWh Utah$160/yr12.9¢/kWh Vermont$290/yr23.3¢/kWh Virginia$198/yr15.9¢/kWh Washington$172/yr13.8¢/kWh West Virginia$184/yr14.8¢/kWh Wisconsin$227/yr18.2¢/kWh Wyoming$160/yr12.8¢/kWh

Based on 1245 kWh/yr (ENERGY STAR rated) at each state's residential electricity rate (EIA, Jan 2026). Click a state for rebates, code requirements, and model rankings.

NWP500S065AUMB in the 65-gallon heat pump class: #3 of 8 on efficiency.

Should this be on your shortlist?

Best for

lightest unit in class, 10-year tank warranty (class-leading)

Why it makes shortlists: top-half efficiency in a 8-model class

Shortlist alternatives in 65-gallon heat pump:

Bradford White RE2HP65-1NCTTUEF 4.2 · 44.6" tall Rheem PROPH65 T2 RH400-30UEF 4.05 · 64.2" tall Rinnai REHP65BMUEF 3.9 · 65.5" tall

Within Navien's 65-gallon heat pump lineup, this page fills a specific role.

Where it sits in the Navien lineup

On efficiency, Navien NWP500S080AUMB sits higher in Navien's 65-gallon heat pump lineup at 4.05 UEF versus 4.03 here.
For heavier simultaneous demand, Navien NWP500S080AUMB is higher at 85 first-hour gallons versus 80 here.
Fit is strongest where height is tight: this is the shortest published option in Navien's 65-gallon heat pump lineup at 63 inches.

Closest same-brand alternatives:

Navien NWP500S050AUMB Navien NWP500S080AUMB

The bill may work. Now check what actually changes on install day before you let the shortlist settle.

Switching to the NWP500S065AUMB

From a standard electric tank

✓

Same voltage (240V). Verify breaker size matches unit requirements (30A typical).

▲

Taller unit (63"). Measure overhead clearance.

▲

Condensate drain needed. Floor drain or condensate pump.

▲

Air space needed around the unit for heat exchange.

Fewest install changes of any upgrade path. Scope depends on existing wiring, clearances, and condensate routing.

From a gas tank

▲

New 240V/30A circuit required. Hire an electrician.

✓

Gas line capped. No more gas bill for hot water.

✓

Existing flue/vent can be removed.

▲

Condensate drain needed.

Two trades needed (plumber + electrician).

From an older heat pump

✓

Same electrical. Same condensate drain.

▲

Check height. This unit is 63" tall.

✓

Standard water connections.

Similar installation profile. Verify dimensions, clearances, and condensate routing match your existing setup.

Height, electrical service, condensate, and noise. These are the four things that determine whether a heat pump fits your space and your quote.

NWP500S065AUMB installation specifications

Dimensions

Height63 in

Width25 in

Depth25 in

Weight204 lbs

Connections3/4 inch NPT

Electrical

Voltage240V

Amperage23A

Breaker30A dedicated

Heat Pump

Min ambient temp41°F

Max ambient temp113°F

RefrigerantR-134a

Noise45 dBA

Safety and installation warnings

These warnings apply to this water heater type. Always follow the manufacturer's installation instructions and local building codes. Hire a licensed professional for installation.

T&P relief valve. Every tank-type water heater has a temperature and pressure relief (T&P) valve. This is a critical safety device that prevents tank rupture by releasing water if temperature exceeds 210°F or pressure exceeds 150 PSI. The discharge pipe must run to within 6 inches of the floor or to an exterior drain. Never cap or plug the T&P valve. Test it annually.

Scald prevention. The recommended maximum water temperature is 120°F to prevent scalding. Higher temperatures (130-140°F) reduce Legionella bacteria risk but require a thermostatic mixing valve at the outlet to deliver safe temperatures at fixtures. Some jurisdictions require mixing valves when the tank is set above 120°F.

Cold-climate performance. Below 41°F ambient air temperature, the heat pump compressor shuts off and the unit falls back to electric resistance heating at much lower efficiency. The rated UEF assumes DOE test conditions (67°F ambient, 58°F inlet water). In cold climates or unconditioned spaces (garages, unfinished basements), actual annual efficiency will be lower than the rated UEF, and energy costs will be higher than the estimates shown above.

Cold exhaust air. Heat pump water heaters extract heat from surrounding air and exhaust cold, dehumidified air. Do not install in a space that is already difficult to heat. The unit will lower the room temperature by several degrees, which may increase HVAC costs or reduce heat pump efficiency in winter.

Common install considerations for heat pump units

What is required depends on your existing installation, local code, and installer preference.

Thermal Expansion Tank Often required by code Check on Amazon (paid link)

Water Heater Drain Pan Often required by code Check on Amazon (paid link)

Earthquake Straps (Seismic Restraints) Often required by code Check on Amazon (paid link)

Full accessories list

Warranty

Coverage

Tank10 yr

Parts10 yr

Labor1 yr

Class rankings: 65-gallon heat pump water heaters

Rankings

Efficiency (UEF) higher is better

#3Top TierEfficiency · 8 models tested

Bradford White RE2HP...

4.2

Rheem PROPH65 T2 RH4...

4.05

Navien NWP500S065AUMB

4.03

Rinnai REHP65BM

3.9

A. O. Smith HPTA-66-2

3.84

A. O. Smith HPTS-66-2

3.7

Bradford White RE2H65T

3.64

Noritz NHP65

3.34

Height shortest to tallest

#4of 8Compactness

Bradford White RE2HP...

44.6"

A. O. Smith HPTA-66-2

61"

A. O. Smith HPTS-66-2

61.5"

Navien NWP500S065AUMB

63"

Bradford White RE2H65T

63.75"

Noritz NHP65

63.8"

Rheem PROPH65 T2 RH4...

64.19"

Rinnai REHP65BM

65.5"

First Hour Rating higher means more hot water

#4of 8Hot Water Delivery

A. O. Smith HPTA-66-2

83 gal

A. O. Smith HPTS-66-2

82 gal

Bradford White RE2HP...

82 gal

Navien NWP500S065AUMB

80 gal

Rinnai REHP65BM

80 gal

Bradford White RE2H65T

79 gal

Rheem PROPH65 T2 RH4...

75 gal

Noritz NHP65

70 gal

⚡

Starting May 2029, new federal standards require heat pump technology for electric water heaters over 35 gallons. Electric tanks 35 gal and under can still use resistance elements. Every heat pump on this list already exceeds the future standard. Read the full DOE 2029 analysis

Common questions about the Navien NWP500S065AUMB

From manufacturer specs, EIA energy data, and DOE regulations.

How much does the NWP500S065AUMB cost to run per year?

~$217/yr at the U.S. average electricity rate. That is roughly $734/yr less than a standard electric tank.

How much hot water does the NWP500S065AUMB deliver?

80 gallons in the first hour from a 61-gallon tank. Suitable for a household of 1 to 3 people at medium draw.

Will the NWP500S065AUMB fit in my space?

63" tall, 25" wide, 25" deep. Measure your space including clearances before ordering.

What electrical circuit does the NWP500S065AUMB need?

240V, 30A dedicated circuit. Check your electrical panel before installation.

Does the NWP500S065AUMB work in cold climates?

The heat pump operates down to 41°F ambient temperature. Below that, it switches to standard electric resistance mode, losing the efficiency advantage. In cold climates, install inside the heated building envelope, not in an unheated garage.

What warranty does the NWP500S065AUMB come with?

10-year tank warranty, 10-year parts. Register with Navien after installation to activate full coverage.

Is the NWP500S065AUMB eligible for rebates?

ENERGY STAR certified heat pump water heater. The federal tax credit (IRA Section 25C, up to $2,000) expired December 31, 2025. State and utility rebates may still apply depending on your location.

Is this unit future-proof under the 2029 DOE standards?

Yes. Starting May 2029, electric water heaters over 35 gallons must use heat pump technology. This unit already exceeds that standard.

Full specifications

Performance
UEF	4.03
First Hour Rating	80 gal
kW Input	5 kW
Draw Pattern	High
Est. Annual Energy	1245 kWh/yr
Capacity
Storage Volume	61 gal
Physical
Height	63 in
Width	25 in
Depth	25 in
Weight	204 lbs
Connections	3/4 inch NPT
Electrical
Voltage	240 V
Amperage	23 A
Breaker	30A dedicated
Heat Pump
Type	240 Volt Integrated HPWH
Min Ambient	41 °F
Max Ambient	113 °F
Refrigerant	R-134a
Sound Level	45 dBA
Warranty
Tank	10 yr
Parts	10 yr
Labor	1 yr
Certifications
ENERGY STAR	Certified
Markets	United States, Canada

Keep the route moving

Other Navien models and the full heat pump guide, if this one isn't the right fit.

NPE-210S2 5.3 GPM condensing tankless
NPE-240S2 5.8 GPM condensing tankless
NWP500S050AUMB 44-gal heat pump
NWP500S080AUMB 74-gal heat pump

Heat Pump guide Sizing guide Installation accessories Replacement cost guide Heat pump vs electric tank Heat pump vs gas tankless Cost in your state All models

Sources. ENERGY STAR, Manufacturer, Navien, Retailer listing. Specs last verified 2026-03-17.Methodology

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