Rheem ProTerra 40 Gal
#13 in 40–50 GallonFull review
A strong 240 V choice with Wi-Fi, widely stocked at Home Depot. GE Profile beats it on efficiency and noise.
Home Depot $2,098$2,098
3.3/5
A non-Midea design with a leak sensor built in and a 10-year tank and parts warranty, sold through plumbing dealers. It is louder than most here.
- 40 galSize
- 3.58UEF
- 66 galFirst hour
- 240 VPower
- 35 °FRuns down to
- 10 yr tankWarranty
See it at Ariston
No store we check sells it online; the maker lists where to buy or who installs it.
Pros
- Built-in leak sensor
- The heat pump keeps running in rooms down to 35 °F
- Built-in Wi-Fi: set schedules and vacation mode from the Ariston NET app
Cons
- No labor cover in the published warranty
- Louder than most at 49.1 dB(A); best kept away from bedrooms
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.
Specifications
| Model number | ARIHPWH-40 |
|---|---|
| Ratings (ENERGY STAR) | |
| Size (nominal) | 40 gal |
| Tank volume (measured) | 37 gal |
| Uniform Energy Factor | 3.58 |
| First-hour rating | 66 gal |
| Draw pattern | Medium |
| Yearly energy use | 907 kWh |
| Heat pump cut-off (low) | 35 °F |
| Sound level | 49.1 dB(A) |
| ENERGY STAR ID | 3942613 |
| Installation | |
| Power | 240 V |
| Circuit | 30 A, 208/240 V |
| Backup element | 4,500 W |
| Operating air range | 36 to 120 °F |
| Minimum room size | 700 cu ft |
| Size | 37.6 in tall, 18.2 in across |
| Refrigerant | R-134a |
| Features | |
| Wi-Fi | Built in |
| App | Ariston NET |
| Demand response port (CTA-2045) | Yes |
| Leak detection | Yes |
| Modes | Comfort, Green, Fast, Electric, Vacation |
| Warranty and models | |
| Warranty | 10 yr tank, 10 yr parts |
| Also sold as | American Standard ASHPWH-40*****, Lennox WHHP040T45MD240S**** |
| Released | 2024-12 |
Alternatives in this size
Senville SENWH-HP 50 Gal
#14 in 40–50 GallonFull review
The lowest checked price for the Midea-built design, for a buyer comfortable with a smaller brand’s warranty terms.
Amazon $1,599.99 Senville $1,599.99$1,599.99
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.
Compare
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