A. O. Smith HESF-50 1**
A. O. Smith HESF-50 1** is in the DOE listing as of Oct 26, 2026.
It has a labeled size of 50 gallons, a certified storage volume of 46 gallons, a certified UEF of 0.92, and a certified first-hour rating of 67 gallons of hot water.
Its advertised UEF of 0.92 from A. O. Smith matches the certified 0.92 (Read Oct 5, 2026).
- Electric storage water heater
- 7 listed models
ENERGY STAR certification does not cover this type of water heater.
Certified figures
- Storage volume
- 46gallons
- UEF
- 0.92Uniform energy factor
- First-hour rating
- 67gallonsHot water in the first hour
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Change your hourAdvertised and certified figures
| Figure | Advertised | Certified | Advertiser | Read |
|---|---|---|---|---|
| Size | 50 gal, nominal size | 46 gal storage volume | A. O. Smith | Read Oct 5, 2026 |
| Size | 46 gal | 46 gal storage volume | A. O. Smith | Read Oct 5, 2026 |
| UEF | 0.92 | 0.92 | A. O. Smith | Read Oct 5, 2026 |
| First-hour rating | 67 gal | 67 gal | A. O. Smith | Read Oct 5, 2026 |
Certified figures by listed model
| Model number | Storage volume (gal) | UEF | First-hour rating (gal) | Recovery efficiency | Draw pattern |
|---|---|---|---|---|---|
| EEA12-50R55DVF 1** | 46 | 0.92 | 67 | 98% | Medium |
| EEA9-50R55DV 1** | 46 | 0.92 | 67 | 98% | Medium |
| EESU-50 1** | 46 | 0.92 | 67 | 98% | Medium |
| EEU6-50R45DV 1** | 46 | 0.92 | 67 | 98% | Medium |
| HESF-50 1** | 46 | 0.92 | 67 | 98% | Medium |
| HESFA-50 1** | 46 | 0.92 | 67 | 98% | Medium |
| PESU-50 1** | 46 | 0.92 | 67 | 98% | Medium |
UEF is the uniform energy factor. A dash means the model has no such figure.
It holds 46 gallons in the test, 4 gallons less than its 50-gallon sold size. It delivers 67 gallons of hot water in the test's first hour. Reheating lets it give 21 gallons beyond the 46 gallons in its tank. Of 477 electric storage models, 51 give more hot water in the first hour. The median electric storage model gives 55 gallons in its first hour.
In tests, 92% of the energy it uses ends up as hot water (UEF 0.92). The daily hot water use in the test, called its draw pattern, was medium. Of 297 electric storage models with the same draw pattern, 81 have a higher UEF and 2 a lower one. Its UEF is the median for its type and draw pattern. The water took in 98% of the energy used to reheat it (its recovery efficiency).
All 7 of its model numbers carry the same certified figures. There are 7 more basic models with the same test figures. Each of the 7 other brands lists one of them.
Also listed as
They carry every figure in the table above.
- Every A. O. Smith basic model
- Every 50-gallon electric storage water heater
- Every electric storage water heater
Not covered
- Changes to an advertised figure after the date beside it.