Ariston ENS30L-*
Ariston ENS30L-* 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 ENS30L-*.
Certified figures
- Storage volume
- 27gallons
- UEF
- 0.93Uniform energy factor
- First-hour rating
- 44gallonsHot water in the first hour
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| Model number | Storage volume (gal) | UEF | First-hour rating (gal) | Recovery efficiency | Draw pattern |
|---|---|---|---|---|---|
| ES30S-S* | 27 | 0.93 | 44 | 98% | Low |
UEF is the uniform energy factor. A dash means the model has no such figure.
It holds 27 gallons in the test, 3 gallons less than its 30-gallon sold size. Over one hour from a full tank, it gave 44 gallons in the test (its first-hour rating). Reheating lets it give 17 gallons beyond the 27 gallons in its tank. Of 477 electric storage models, 392 give more hot water in the first hour. Among electric storage models, the median first-hour rating is 55 gallons.
In tests, 93% of the energy went to hot water, so its UEF is 0.93. Its test ran at the low level of daily hot water use. Its UEF is lower than that of 2 of the 157 electric storage models with its draw pattern. For its type and draw pattern, the median UEF is 0.92. Of the energy spent to reheat water, 98% goes into it (its recovery efficiency).
Its test figures match those of 2 other basic models. Those basic models are sold with AMERICAN STANDARD WATER HEATERS and Lennox as their brand names. For the full group, see the AMERICAN STANDARD WATER HEATERS ENS30L-* page.
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.