Friedrich RTGH-S10I vs Noritz EZ98DV (GQ-C2861WX-FF US): which uses less energy?
At the high draw pattern the Noritz EZ98DV (GQ-C2861WX-FF US) uses 173 therms a year and the Friedrich RTGH-S10I 176 — 4 therms (2%) less, about 36 therms over ten years. Both are filed as a gas 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 a gas tankless unit at the high draw pattern.
| Figure | Friedrich RTGH-S10I | Noritz EZ98DV (GQ-C2861WX-FF US) |
|---|---|---|
| UEF (Uniform Energy Factor) | 0.96 | 0.98 (better) |
| Energy use per year (therms) | 176 | 173 (better) |
| Max flow (GPM) | 5.2 | 5.3 |
| Installed cost range NLR REMDB | $2,405–$3,460 | $2,499–$3,570 |
| ENERGY STAR certified ENERGY STAR | yes | yes |
| On the market since ENERGY STAR | 2022-08-01 | 2024-10-01 |
| CPSC recall naming it CPSC | none on file | none on file |
DOE CCD · 2026-09-19 NLR REMDB · 2026-04-01 ENERGY STAR · 2026-09-19 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).
- 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 Friedrich RTGH-S10I since 2022-08-01, the Noritz EZ98DV (GQ-C2861WX-FF US) since 2024-10-01. A sale date, not a lifespan.
Which should you pick?
- Pick the Noritz EZ98DV (GQ-C2861WX-FF US) if running cost matters most: it uses 4 therms less a year on the same test.
- Pick the Friedrich RTGH-S10I if it is the one you can get installed sooner or for less — on the filed figures it has no advantage over the Noritz EZ98DV (GQ-C2861WX-FF US).
- Neither if you need more than 5.3 GPM at the same time — neither unit lists more. Check how to size a tankless unit by GPM.
Each model on its own
- Friedrich RTGH-S10I 176 therms a year
- Noritz EZ98DV (GQ-C2861WX-FF US) 173 therms a year