ARISTON ARIHPWH-50-T vs Novair US3-RSJ-15/190RDVN3-L3: which uses less energy?
At the medium draw pattern the ARISTON ARIHPWH-50-T uses 848 kWh a year and the Novair US3-RSJ-15/190RDVN3-L3 866 — 18 kWh (2%) less, about 181 kWh over ten years. Both are filed as an electric tank, so the comparison holds. Enter your ZIP below to price the difference.
Side by side
Compared within one class only: models filed as an electric tank at the medium draw pattern.
| Figure | ARISTON ARIHPWH-50-T | Novair US3-RSJ-15/190RDVN3-L3 |
|---|---|---|
| UEF (Uniform Energy Factor) | 3.83 (better) | 3.75 |
| Energy use per year (kWh) | 848 (better) | 866 |
| First hour rating (gal) | 69 | 69 |
| Rated storage volume (gal) | 45 | 47 |
| Installed cost range | $3,033–$4,480 | $3,089–$4,419 |
| ENERGY STAR certified | yes | yes |
| Sound level (dB) | not filed | 49 |
| Refrigerant | R-513A, GWP 630 | R-134a, GWP 1430 |
| On the market since | 2025-06-01 | 2025-05-01 |
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.
- Both are ENERGY STAR certified, which requires a manufacturer warranty of at least six years; the actual term for each model is not published.
- Time on the market, as filed with ENERGY STAR: the ARISTON ARIHPWH-50-T since 2025-06-01, the Novair US3-RSJ-15/190RDVN3-L3 since 2025-05-01. A sale date, not a lifespan.
Which should you pick?
- Pick the ARISTON ARIHPWH-50-T if running cost matters most: it uses 18 kWh less a year on the same test.
- Pick the Novair US3-RSJ-15/190RDVN3-L3 if it is the one you can get installed sooner or for less — on the filed figures it has no advantage over the ARISTON ARIHPWH-50-T.
- Neither if your household's busiest hour needs more than 69 gallons of hot water — neither lists more. Check whether a 40-gallon heater is enough.
Each model on its own
-
ARISTON ARIHPWH-50-T
Its filed figures, class position and running cost on your ZIP.
-
Novair US3-RSJ-15/190RDVN3-L3
Its filed figures, class position and running cost on your ZIP.