Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.
Stiebel Eltron Tempra 36 Plus comes out ahead by a narrow margin (4.7 vs 4.8). The gap is mostly about whole-home electric tankless installs in mild climates — read the strengths below before deciding.
The RTEX-24 is the cold-climate pick — Rheem's flagship that handles northern winter inlet temps better than competitors.
The Tempra 36 Plus is the best-overall pick — Stiebel Eltron's flow control handles whole-home demand without cold-water sandwiching.
Best for cold climates. Most user reviews. Cheaper than Tempra.
Best whole-home pick. German engineering. Highest amperage required.
| Spec | Rheem RTEX-24 | Stiebel Eltron Tempra 36 Plus |
|---|---|---|
| Type | Electric whole-home | Electric whole-home |
| Power | 24 kW | 36 kW |
| Self-Modulating | Yes | — |
| Reviews | 3,900+ | — |
| Flow Control | — | Advanced |
| Warranty | — | 10-year combined |