Navien NWP500 50 Gal vs Rheem ProTerra 50 Gal

Last updated: October 22, 2026

The Rheem ProTerra 50 Gal is the better heat pump water heater overall, rated 3.7 to 3.4. The Rheem ProTerra 50 Gal leads on cold rooms and hot water.

Navien NWP500 50 Gal vs Rheem ProTerra 50 Gal

Navien NWP500 50 Gal

Navien’s stainless-tank hybrid, sold through plumbers, with a 10-year warranty that includes a year of labor. Its heat pump stops below 41 °F room air, so it suits a basement more than a cold garage.

Prices were last checked October 21, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.

Which should you buy?

Scores side by side

Each factor is scored 0-100 against the same fixed reference points for every 40–50 gallon heat pump water heater; a clear win is highlighted. How we rank explains each one.

Factor weightRheem ProTerra 50 GalNavien NWP500 50 Gal
Overall rating3.7/53.4/5
Efficiency 35%63 3.88 UEF61 3.85 UEF
Hot water 20%68 67 gallons in the first hour60 65 gallons in the first hour
Warranty 20%75 10-year tank, 10-year parts, 1-year labor75 10-year tank, 10-year parts, 1-year labor
Cold rooms 15%32 heat pump runs down to 37 °F room air16 heat pump runs down to 41 °F room air
Noise 10%69 45 dB(A)50 noise not published (neutral score used)

Specifications

Rheem ProTerra 50 GalNavien NWP500 50 Gal
Ratings (ENERGY STAR)
Size (nominal)50 gal50 gal
Tank volume (measured)45 gal44 gal
Uniform Energy Factor3.883.85
First-hour rating67 gal65 gal
Draw patternMediumMedium
Yearly energy use846 kWh840 kWh
Heat pump cut-off (low)37 °F41 °F
Sound level45 dB(A)-
ENERGY STAR ID35542024015938
Installation
Power240 V240 V
Circuit30 A, 208/240 V30 A, 208/240 V
Backup element4,500 W5,000 W
Operating air range37 to 145 °F41 to 113 °F
Minimum room size700 cu ft640 cu ft
Size61.8 in tall, 22.3 in across63 in tall, 21.8 in across
Weight185 lb181 lb
RefrigerantR-134aR-134a
Features
Wi-FiBuilt inBuilt in
AppEcoNetNaviLink
Demand response port (CTA-2045)Yes-
Leak detectionNoNo
ModesEnergy Saver, Heat Pump, High Demand, Electric, VacationEnergy Saver, Heat Pump, High Demand, Electric, Vacation
Warranty and models
Warranty10 yr tank, 10 yr parts, 1 yr labor10 yr tank, 10 yr parts, 1 yr labor
Also sold asFriedrich PROH50 T2 FD400-30, Friedrich PROH50 T2 FD400-SO, Rheem PROPH50 T2 RH375-30, Rheem PROPH50 T2 RH400-30, Rheem PROPH50 T2 RH400-SO, Richmond 10E50-HP530, Richmond 10E50-HP5U30, Richmond 10E50-HP5US30, Ruud PROUH50 T2 RU375-30, Ruud PROUH50 T2 RU375-SO, Ruud PROUH50 T2 RU400-30, Ruud PROUH50 T2 RU400-SO-
Released2024-062025-06