Eemax SPEX75 vs Rheem SPEX80T: which uses less energy?
At the very small draw pattern the Rheem SPEX80T uses 603 kWh a year and the Eemax SPEX75 615 — 13 kWh (2%) less, about 126 kWh over ten years. Both are filed as an electric tankless unit, 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 tankless unit at the very small draw pattern.
| Figure | Eemax SPEX75 | Rheem SPEX80T |
|---|---|---|
| UEF (Uniform Energy Factor) | 0.96 | 0.98 (better) |
| Energy use per year (kWh) | 615 | 603 (better) |
| Max flow (GPM) | 0.8 | 0.8 |
| Installed cost range NLR REMDB | $1,306–$1,838 | $1,311–$1,886 |
| 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?
- Pick the Rheem SPEX80T if running cost matters most: it uses 13 kWh less a year on the same test.
- Pick the Eemax SPEX75 if it is the one you can get installed sooner or for less — on the filed figures it has no advantage over the Rheem SPEX80T.
- Neither if you need more than 0.8 GPM at the same time — neither unit lists more. Check how to size a tankless unit by GPM.
Each model on its own
- Eemax SPEX75 615 kWh a year
- Rheem SPEX80T 603 kWh a year