Rinnai REHP50
#4 in 40–50 GallonFull review
A Midea-built heater with Rinnai’s support network and one of the few listings on Amazon. Check the seller is a Rinnai-authorized dealer before buying.
Amazon $1,799 Lowe's $1,799$1,799
The Rinnai REHP50 is the better heat pump water heater overall, rated 3.6 to 3.1. The Rinnai REHP50 leads on hot water. The Rheem ProTerra 15 A 50 Gal wins on noise.
Rheem ProTerra 15 A 50 Gal
#16 in 40–50 GallonFull review
The ProTerra for a home that only has a 15 A, 240 V circuit, such as one left by a small electric tank: it avoids rewiring but gives up some efficiency and first-hour delivery.
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?
- Choose the Rinnai REHP50 for hot water (73 gallons in the first hour vs 52 gallons in the first hour).
- Choose the Rheem ProTerra 15 A 50 Gal for noise (45 dB(A) vs 49 dB(A)).
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 weight | Rinnai REHP50 | Rheem ProTerra 15 A 50 Gal |
|---|---|---|
| Overall rating | 3.6/5 | 3.1/5 |
| Efficiency 35% | 54 3.75 UEF | 54 3.75 UEF |
| Hot water 20% | 92 73 gallons in the first hour | 8 52 gallons in the first hour |
| Warranty 20% | 75 10-year tank, 10-year parts, 1-year labor | 75 10-year tank, 10-year parts, 1-year labor |
| Cold rooms 15% | 30 heat pump runs down to 37.4 °F room air | 32 heat pump runs down to 37 °F room air |
| Noise 10% | 44 49 dB(A) | 69 45 dB(A) |
Specifications
| Rinnai REHP50 | Rheem ProTerra 15 A 50 Gal | |
|---|---|---|
| Ratings (ENERGY STAR) | ||
| Size (nominal) | 50 gal | 50 gal |
| Tank volume (measured) | 46 gal | 45 gal |
| Uniform Energy Factor | 3.75 | 3.75 |
| First-hour rating | 73 gal | 52 gal |
| Draw pattern | Medium | Medium |
| Yearly energy use | 844 kWh | 846 kWh |
| Heat pump cut-off (low) | 37.4 °F | 37 °F |
| Sound level | 49 dB(A) | 45 dB(A) |
| ENERGY STAR ID | 3531243 | 3554192 |
| Installation | ||
| Power | 240 V | 240 V |
| Circuit | 30 A, 208/240 V | 15 A, 208/240 V |
| Backup element | 4,500 W | 2,250 W |
| Operating air range | 37 to 107 °F | 37 to 145 °F |
| Minimum room size | 700 cu ft | 700 cu ft |
| Size | 66.4 in tall, 21.7 in across | 61.8 in tall, 22.3 in across |
| Weight | 218 lb | 185 lb |
| Refrigerant | R-134a | R-134a |
| Features | ||
| Wi-Fi | No | Built in |
| App | - | EcoNet |
| Demand response port (CTA-2045) | - | Yes |
| Leak detection | No | No |
| Modes | Economy, Heat Pump, Hybrid, E-Heater, Vacation | Energy Saver, Heat Pump, High Demand, Electric, Vacation |
| Warranty and models | ||
| Warranty | 10 yr tank, 10 yr parts, 1 yr labor | 10 yr tank, 10 yr parts, 1 yr labor |
| Also sold as | - | Friedrich PROH50 T2 FD400-15, Rheem PROPH50 T2 RH375-15, Rheem PROPH50 T2 RH400-15, Richmond 10E50-HP515, Richmond 10E50-HP5U15, Ruud PROUH50 T2 RU375-15, Ruud PROUH50 T2 RU400-15 |
| Released | 2024-08 | 2024-06 |