Ariston ENS30LUB*
Ariston ENS30LUB* is in the DOE listing as of Oct 19, 2026.
- Electric storage water heater
- 1 listed model
ENERGY STAR certification does not cover this type of water heater.
Its figures are also listed under AMERICAN STANDARD WATER HEATERS ENS30LUB*.
Certified figures
- Storage volume
- 28gallons
- UEF
- 0.92Uniform energy factor
- First-hour rating
- 40gallonsHot water in the first hour
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| Model number | Storage volume (gal) | UEF | First-hour rating (gal) | Recovery efficiency | Draw pattern |
|---|---|---|---|---|---|
| ESB30S* | 28 | 0.92 | 40 | 98% | Low |
UEF is the uniform energy factor. A dash means the model has no such figure.
It holds 28 gallons in the test, 2 gallons less than its 30-gallon sold size. Over one hour from a full tank, it gave 40 gallons in the test (its first-hour rating). That is 12 gallons more than its tank holds, since it reheats during the hour. Of 477 electric storage models, 444 give more hot water in the first hour. The median electric storage model gives 55 gallons in the first hour of the test.
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 low. Of 157 electric storage models with the same draw pattern, 12 have a higher UEF and 76 a lower one. On its draw pattern, its UEF is also the median electric storage UEF. 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. Of those, one or more are under the AMERICAN STANDARD WATER HEATERS and Lennox brands. For the full group, see the AMERICAN STANDARD WATER HEATERS ENS30LUB*.
Also listed as
They carry every figure in the table above.
- Every Ariston basic model
- Every 30-gallon electric storage water heater
- Every electric storage water heater
Not covered
- Advertised figures. We have none on file for this model.