A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2)
A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) is a heat pump (hybrid electric) water heater from A. O. Smith with a 36 gallon rated tank and a 55 gallon first-hour rating at a 3.6 UEF.
| Uniform Energy Factor (UEF) | 3.6 |
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| Annual electricity use | 902 kWh/yr |
| Recovery efficiency | 426 % |
| Fuel | Electric |
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| First-hour rating | 55 gal |
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| Rated storage volume | 36 gal |
| Draw pattern | Medium |
| Heat pump type | 240 Volt Integrated HPWH |
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| Refrigerant (GWP) | R-134a (GWP:1430) |
| Compressor low-temp cutoff | 37 °F |
| Input voltage | 240 |
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| Max current draw | 22 A |
| Smart / connected capable | Yes |
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| Height | 66 in |
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| Diameter | 20 in |
| ENERGY STAR certified | Yes |
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Who is the A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) for?
- Its 55 gallon first-hour rating suits a household of 2–3 people under DOE sizing guidance.
- Estimated running cost: about $153/year at the national average electricity rate (902 kWh/yr certified use).
- Needs a 240 V circuit; at 22 A max draw plan for a 30 A breaker (NEC 125% continuous-load rule).
- The heat pump compressor operates down to 37 °F ambient — below that, backup elements take over.
Similar water heaters
- A. O. Smith Heat Pump 40-Gallon (HPTA-40 2) (UEF 3.6)
- American Heat Pump 40-Gallon (UEF 3.6)
- Friedrich Heat Pump 50-Gallon (PROH50 T0 FD120-M) (UEF 3)
- Friedrich Heat Pump 50-Gallon (PROH50 T0 FD120-MSO) (UEF 3)
- Lochinvar Heat Pump 40-Gallon (UEF 3.6)
- RELIANCE WATER HEATERS Heat Pump 40-Gallon (UEF 3.6)
Frequently asked questions
Is the A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) ENERGY STAR certified?
Yes, the A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) holds a current ENERGY STAR certification for water heating efficiency (UEF 3.6).
How much does the A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) cost to run per year?
About $153 per year at national average energy rates, based on its certified annual energy use under the DOE test draw pattern. Your rate and usage change this figure.
What electrical circuit does the A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) need?
The A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) runs on a 240 V circuit drawing up to 22 A; per the NEC 125% continuous-load rule plan for at least a 30 A breaker (check the installation manual for the required circuit).
Is the A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) a smart water heater?
Yes, the A. O. Smith Heat Pump 40-Gallon (HPA10-40H45DV 2) is connected-capable, with app control and eligibility for most utility demand-response programs.
Sources
- data.energystar.gov (retrieved 2026-07-17)