AMERICAN STANDARD WATER HEATERS ENS40LU-*
AMERICAN STANDARD WATER HEATERS ENS40LU-* is in the DOE listing as of Oct 26, 2026.
It has a labeled size of 38 gallons, a certified storage volume of 36 gallons, a certified UEF of 0.91, and a certified first-hour rating of 41 gallons of hot water.
Its advertised UEF of 0.91 from AMERICAN STANDARD WATER HEATERS matches the certified 0.91 (Read Oct 5, 2026).
- Electric storage water heater
- 1 listed model
ENERGY STAR certification does not cover this type of water heater.
Certified figures
- Storage volume
- 36gallons
- UEF
- 0.91Uniform energy factor
- First-hour rating
- 41gallonsHot water in the first hour
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| Figure | Advertised | Certified | Advertiser | Read |
|---|---|---|---|---|
| Size | 38 gal, nominal size | 36 gal storage volume | AMERICAN STANDARD WATER HEATERS | Read Oct 5, 2026 |
| Size | 36 gal | 36 gal storage volume | AMERICAN STANDARD WATER HEATERS | Read Oct 5, 2026 |
| UEF | 0.91 | 0.91 | AMERICAN STANDARD WATER HEATERS | Read Oct 5, 2026 |
| First-hour rating | 41 gal | 41 gal | AMERICAN STANDARD WATER HEATERS | Read Oct 5, 2026 |
Certified figures by listed model
| Model number | Storage volume (gal) | UEF | First-hour rating (gal) | Recovery efficiency | Draw pattern |
|---|---|---|---|---|---|
| ENS40LU-* | 36 | 0.91 | 41 | 98% | Low |
UEF is the uniform energy factor. A dash means the model has no such figure.
It holds 36 gallons in the test, 2 gallons less than its 38-gallon sold size. Over one hour from a full tank, it gave 41 gallons in the test (its first-hour rating). That is 5 gallons more than its tank holds, since it reheats during the hour. Of 477 electric storage models, 429 give more hot water in the first hour. The median electric storage model gives 55 gallons in its first hour.
In tests, 91% of the energy went to hot water, so its UEF is 0.91. Its test ran at the low level of daily hot water use. Its UEF is lower than that of 81 of the 157 electric storage models with its draw pattern. For its type and draw pattern, the UEF runs from 0.88 to 0.95. The water took in 98% of the energy used to reheat it (its recovery efficiency).
Its test figures match those of 2 other basic models. The Ariston and Lennox brands list one or more of them.
Also listed as
They carry every figure in the table above.
- Every AMERICAN STANDARD WATER HEATERS basic model
- Every 40-gallon electric storage water heater
- Every electric storage water heater
Not covered
- Changes to an advertised figure after the date beside it.