The Midea-built design, sold direct by an online HVAC store, for a buyer installing it themselves who doesn’t need labor cover.
Amazon $1,799.99 ACiQ
A solid 240 V heater with leak protection included, sold at Lowe’s as the Signature 900 line.
- 50 galSize
- 3.68UEF
- 65 galFirst hour
- 240 VPower
- 37 °FRuns down to
- 10 yr tankWarranty
Price checked October 21, 2026. As an Amazon Associate we earn from qualifying purchases.
- Comes with a leak sensor and automatic shut-off valve
- Built-in Wi-Fi: set schedules and vacation mode from the A. O. Smith (iCOMM) app
- 10-year tank and parts warranty plus 1 year of labor
- Switches to the backup element when the room drops below 37 °F, so it saves little in a freezing garage
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 | HPTA-50 |
|---|---|
| Ratings (ENERGY STAR) | |
| Size (nominal) | 50 gal |
| Tank volume (measured) | 46 gal |
| Uniform Energy Factor | 3.68 |
| First-hour rating | 65 gal |
| Draw pattern | Medium |
| Yearly energy use | 883 kWh |
| Heat pump cut-off (low) | 37 °F |
| Sound level | 45 dB(A) |
| ENERGY STAR ID | 3417485 |
| Installation | |
| Power | 240 V |
| Circuit | 30 A, 208/240 V |
| Backup element | 4,500 W |
| Operating air range | 37 to 120 °F |
| Minimum room size | 450 cu ft |
| Size | 63 in tall, 15 in across |
| Weight | 196 lb |
| Refrigerant | R-134a |
| Features | |
| Wi-Fi | Built in |
| App | A. O. Smith (iCOMM) |
| Demand response port (CTA-2045) | Yes |
| Leak detection | Yes |
| Modes | Hybrid, Heat Pump, Hot Water+ (3 levels), Guest, Electric, Vacation |
| Warranty and models | |
| Warranty | 10 yr tank, 10 yr parts, 1 yr labor |
| Also sold as | American HPA10250H045DV, Lochinvar HPPA050KD, Reliance 10-50-DHPTA, State HPAX-50-DHPT |
| Released | 2024-03 |
Alternatives in this size
The Midea original behind several heaters here, sold through HVAC contractors. Buy whichever version is easiest to get with the warranty you want.
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.
Compare
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