A.O. Smith Voltex MAX 50 Gal
#11 in 40–50 GallonFull review
A solid 240 V heater with leak protection included, sold at Lowe’s as the Signature 900 line.
Lowe's $2,229$2,229
The A.O. Smith Voltex MAX 50 Gal rates 3.4 among 40–50 gallon heat pump water heaters; the A.O. Smith Voltex 120V 66 Gal rates 3.1 among 65 gallon ones. The A.O. Smith Voltex MAX 50 Gal costs $469 less ($2,229 vs $2,698).
A.O. Smith Voltex 120V 66 Gal
#14 in 65 GallonFull review
A 120 V plug-in with a backup element and leak shut-off included. Its certified efficiency is among the lowest here, so it suits replacing a gas tank more than replacing an electric one.
Lowe's $2,698$2,698
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.
Scores side by side
These two sit in different size classes (40–50 gallon and 65 gallon), and each is scored against the reference points for its own class, so a rating says how well each does among its own size peers. How we rank explains each factor.
| Factor weight | A.O. Smith Voltex MAX 50 Gal | A.O. Smith Voltex 120V 66 Gal |
|---|---|---|
| Overall rating | 3.4/5 | 3.1/5 |
| Efficiency 35% | 49 3.68 UEF | 14 3.20 UEF |
| Hot water 20% | 60 65 gallons in the first hour | 64 76 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% | 32 heat pump runs down to 37 °F room air | 32 heat pump runs down to 37 °F room air |
| Noise 10% | 69 45 dB(A) | 69 45 dB(A) |
Specifications
| A.O. Smith Voltex MAX 50 Gal | A.O. Smith Voltex 120V 66 Gal | |
|---|---|---|
| Ratings (ENERGY STAR) | ||
| Size (nominal) | 50 gal | 66 gal |
| Tank volume (measured) | 46 gal | 68 gal |
| Uniform Energy Factor | 3.68 | 3.20 |
| First-hour rating | 65 gal | 76 gal |
| Draw pattern | Medium | High |
| Yearly energy use | 883 kWh | 1,550 kWh |
| Heat pump cut-off (low) | 37 °F | 37 °F |
| Sound level | 45 dB(A) | 45 dB(A) |
| ENERGY STAR ID | 3417485 | 2546252 |
| Installation | ||
| Power | 240 V | Plug-in 120 V |
| Circuit | 30 A, 208/240 V | Shared 15 A circuit |
| Backup element | 4,500 W | 900 W |
| Operating air range | 37 to 120 °F | 37 to 120 °F |
| Minimum room size | 450 cu ft | 450 cu ft |
| Size | 63 in tall, 15 in across | 61 in tall, 23 in across |
| Weight | 196 lb | 289 lb |
| Refrigerant | R-134a | R-513A |
| Features | ||
| Wi-Fi | Built in | Built in |
| App | A. O. Smith (iCOMM) | A. O. Smith (iCOMM) |
| Demand response port (CTA-2045) | Yes | Yes |
| Leak detection | Yes | Yes |
| Modes | Hybrid, Heat Pump, Hot Water+ (3 levels), Guest, Electric, Vacation | Heat Pump, 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 | American HPA10250H045DV, Lochinvar HPPA050KD, Reliance 10-50-DHPTA, State HPAX-50-DHPT | American HPV10266H009DV, Lochinvar HPV065KD, Reliance 10-66-DHPTV, State HPVX-66-DHPT |
| Released | 2024-03 | 2023-07 |