A. O. Smith ENLB-40 1** vs Reliance ENL-36 2**: which uses less energy?
An asterisk in a model number stands for any character: one filing covers several variants.
At the medium draw pattern the A. O. Smith ENLB-40 1** and the Reliance ENL-36 2** use the same energy, 3,531 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 medium draw pattern.
| Figure | A. O. Smith ENLB-40 1** | Reliance ENL-36 2** |
|---|---|---|
| UEF (Uniform Energy Factor) | 0.92 | 0.92 |
| Energy use per year (kWh) | 3,531 | 3,531 |
| First hour rating (gal) | 51 | 51 |
| Rated storage volume (gal) | 35 | 33 |
| Installed cost range NLR REMDB | $1,576–$1,777 | $1,548–$1,727 |
| CPSC recall naming it CPSC | none on file | none on file |
DOE CCD · 2026-09-19 NLR REMDB · 2026-04-01 CPSC · 2026-09-24
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 above.
- No CPSC recall on file names either model (list checked 2026-09-24).
- The actual warranty term is printed in each model’s documentation, not in any registry.
Which should you pick?
- Either one: On filed figures these are interchangeable; decide on installed price and availability.
- Neither if your household's busiest hour needs more than 51 gallons of hot water — neither lists more. Check whether a 30-gallon heater is enough.
Each model on its own
- A. O. Smith ENLB-40 1** 3,531 kWh a year
- Reliance ENL-36 2** 3,531 kWh a year