Best Tankless Water Heaters · head-to-head

Rinnai RU199iN vs Stiebel Eltron Tempra 36 Plus

A sourced, side-by-side comparison. Stiebel Eltron Tempra 36 Plus is cheaper at $1132. Every spec and price links to its source.

Which is better: the Rinnai RU199iN or Stiebel Eltron Tempra 36 Plus?

The Stiebel Eltron Tempra 36 Plus wins 1 of the 1 specs we compare head to head; the other wins 0.

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Full spec sheet

✓ marks the stronger figure where "more" — or "less", for price and weight — is unambiguously better.

Spec Rinnai RU199iN Stiebel Eltron Tempra 36 Plus
US price — $1132
BrandRinnaiStiebel Eltron
Released——
Fuel type natural-gas electric
Max flow rate (gpm) 11 8.2
Max btu per hour 199000 —
Power input (kW) — 36
Uniform energy factor 0.95 —
Condensing type condensing electric
Min activation flow (gpm) — 0.77
Vent type — none
Max temp (°F) — 140
Heat exchanger warranty yrs 15 7
Wi-Fi enabled No No
Weight (lb) 64 17.6

Sources — Rinnai RU199iN: rinnai.us (verified 2026-07-11). Stiebel Eltron Tempra 36 Plus: stiebel-eltron-usa.com (verified 2026-07-11).

What's the difference between the Rinnai RU199iN and Stiebel Eltron Tempra 36 Plus?

Where the two actually differ on the specs we track (5 of 12). Matching specs are omitted.

  • Fuel type: Rinnai RU199iN natural-gas vs Stiebel Eltron Tempra 36 Plus electric
  • Max flow rate (gpm): Rinnai RU199iN 11 vs Stiebel Eltron Tempra 36 Plus 8.2
  • Condensing type: Rinnai RU199iN condensing vs Stiebel Eltron Tempra 36 Plus electric
  • Heat exchanger warranty yrs: Rinnai RU199iN 15 vs Stiebel Eltron Tempra 36 Plus 7
  • Weight (lb): Rinnai RU199iN 64 vs Stiebel Eltron Tempra 36 Plus 17.6

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