A. O. SMITH MHE6-40RW-035D-1** vs ARISTON ENS40LU-*: which uses less energy?
At the low draw pattern the A. O. SMITH MHE6-40RW-035D-1** and the ARISTON ENS40LU-* use the same energy, 2,466 kWh a year each, on the same federal test. Both are filed as an electric tank, so the comparison holds; what separates them is below. Enter your ZIP to price either one on your own rate.
Side by side
Compared within one class only: models filed as an electric tank at the low draw pattern.
| Figure | A. O. SMITH MHE6-40RW-035D-1** | ARISTON ENS40LU-* |
|---|---|---|
| UEF (Uniform Energy Factor) | 0.91 | 0.91 |
| Energy use per year (kWh) | 2,466 | 2,466 |
| First hour rating (gal) | 40 | 41 |
| Rated storage volume (gal) | 36 | 36 |
| Installed cost range | not published | not published |
| ENERGY STAR certified | not matched | not matched |
What it costs to run
Reliability
Not published: Reliability, failure rates and each model’s actual warranty term.
The registries these figures come from certify energy performance under a federal test; none of them records how long a unit lasts or how often it fails, so this page does not rank the two on reliability.
What is here instead:
- The filed efficiency, capacity and tank size of both models, side by side below.
- The actual warranty term is printed in each model’s documentation, not in any registry.
Which should you pick?
- Pick the A. O. SMITH MHE6-40RW-035D-1** if its price or availability suits you — on energy the two are level.
- Pick the ARISTON ENS40LU-* if you need more hot water in your busiest hour: it lists a first hour rating of 41 gallons against 40.
- Neither if your household's busiest hour needs more than 41 gallons of hot water — neither lists more. Check whether a 40-gallon heater is enough.
Each model on its own
-
A. O. SMITH MHE6-40RW-035D-1**
Its filed figures, class position and running cost on your ZIP.
-
ARISTON ENS40LU-*
Its filed figures, class position and running cost on your ZIP.