waterheaterspecs

Gas tankless · high draw

Rinnai (CXxxI) REU-NBxxFFC-US

The Rinnai (CXxxI) REU-NBxxFFC-US line holds two certified rating sets of gas tankless water heaters, 8 model numbers sold as Rinnai, listed by Rinnai America. Gas input runs from 160,000 to 199,000 Btu/h, and max flow at a 67 °F rise runs from 4.6 to 5.8 gal/min. Rinnai (CX199I) REU-NB3237FFC-US lists 5.8 gal/min, the fifth highest of the 40 gas tankless sets (shared by three sets). Rinnai (CX199I) REU-NB3237FFC-US, the set with the most model numbers, rates 0.02 above the median UEF of the 39 high-draw gas tankless sets (0.96).

Certified as of October 27, 2026 · EPA ENERGY STAR data, public domain · Compare in the Heater finder

Size by size

Certified values of Rinnai (CXxxI) REU-NBxxFFC-US
Rating setGas input, Btu/hMax flow, gal/minShare of heat ceilingUEFUEF rankTherms/yr
Rinnai (CX160I) REU-NB2530FFC-US4 model numbers160,0004.696%0.97 highseventh highest of 39175
Rinnai (CX199I) REU-NB3237FFC-US4 model numbers199,0005.898%0.98 highhighest of 39, six tied173

Share of heat ceiling: listed flow ÷ the flow the gas input could heat through 67 °F at 100% efficiency; test tolerances allow a little over 100%.

Rinnai (CXxxI) REU-NBxxFFC-US: max flow against gas input

Rinnai (CXxxI) REU-NBxxFFC-USOther gas tankless sets

Max flow at a 67 °F rise, gal/min

Rinnai (CXxxI) REU-NBxxFFC-US: max flow against gas input3.54.04.55.05.56.06.5120130140150160170180190200Gas input, thousand Btu/hA. O. Smith ACT-199O-N 1A. O. Smith ATHR-160M 1A. O. Smith ATHR-180M 1A. O. Smith ATHR-199M 1A. O. Smith ATI-340H 1A. O. Smith ATM-140M-N 1A. O. Smith ATM-199M-N 1A. O. Smith ATO-240H 1Bosch T9800 SE 160Bosch T9800 SE 199Bradford White RTGR150N1Kepler JSG48-29PCH/180KKepler JSG52-32PCH/199KNPMidea JSG40-24PCH-LPMidea JSG48-29PCH-LPMidea JSG52-32PCH-LPMidea MGWH150IXNNNavien NPE-180A2Navien NPE-180S2Navien NPE-210A2Navien NPE-210S2Navien NPE-240A2Noritz EZ111DV (GQ-C3260WX-FF US)Noritz EZ111DV (GQ-C3261WX-FF US)Noritz EZ71DV (GQ-C2661WX-FF US)Noritz EZ98DV (GQ-C2860WX-FF US)Noritz EZ98DV (GQ-C2861WX-FF US)Noritz NRCR92DV (GQ-C2660WXQ-FF US)Noritz NRCR92DV (GQ-C2661WXQ-FF US)Rheem ECOHS160INRheem ECOHS180INRheem ECOHS200INRinnai (RX130I) REU-NB2024FF-USVesta VRP-PLUS-150Vesta VRS PLUS-199Vesta VTP-150Vesta VTP-199Vesta VTS-150Rinnai (CX160I) REU-NB2530FFC-USRinnai (CX199I) REU-NB3237FFC-US
Rinnai (CXxxI) REU-NBxxFFC-US: max flow against gas input3.54.04.55.05.56.06.5120140160180200Gas input, thousand Btu/hA. O. Smith ACT-199O-N 1A. O. Smith ATHR-160M 1A. O. Smith ATHR-180M 1A. O. Smith ATHR-199M 1A. O. Smith ATI-340H 1A. O. Smith ATM-140M-N 1A. O. Smith ATM-199M-N 1A. O. Smith ATO-240H 1Bosch T9800 SE 160Bosch T9800 SE 199Bradford White RTGR150N1Kepler JSG48-29PCH/180KKepler JSG52-32PCH/199KNPMidea JSG40-24PCH-LPMidea JSG48-29PCH-LPMidea JSG52-32PCH-LPMidea MGWH150IXNNNavien NPE-180A2Navien NPE-180S2Navien NPE-210A2Navien NPE-210S2Navien NPE-240A2Noritz EZ111DV (GQ-C3260WX-FF US)Noritz EZ111DV (GQ-C3261WX-FF US)Noritz EZ71DV (GQ-C2661WX-FF US)Noritz EZ98DV (GQ-C2860WX-FF US)Noritz EZ98DV (GQ-C2861WX-FF US)Noritz NRCR92DV (GQ-C2660WXQ-FF US)Noritz NRCR92DV (GQ-C2661WXQ-FF US)Rheem ECOHS160INRheem ECOHS180INRheem ECOHS200INRinnai (RX130I) REU-NB2024FF-USVesta VRP-PLUS-150Vesta VRS PLUS-199Vesta VTP-150Vesta VTP-199Vesta VTS-150Rinnai (CX160I) REU-NB2530FFC-USRinnai (CX199I) REU-NB3237FFC-US
Filled: the two sets of Rinnai (CXxxI) REU-NBxxFFC-US; open circles: the other 38 gas tankless sets. Dashed line: the flow that the full gas input could heat through a 67 °F rise.

Across the sizes

Moving from 160,000 Btu/h to 199,000 Btu/h of gas input lifts max flow from 4.6 gal/min to 5.8 gal/min, about 0.31 gal/min for each extra 10,000 Btu/h.

Strongest placings, size by size

MeasureValueMedian of the groupPlacingCompared with
UEFRinnai (CX160I) REU-NB2530FFC-US0.970.96seventh highest of 3939 high-draw gas tankless sets
Rated gas useRinnai (CX160I) REU-NB2530FFC-US175 therms/yr176 therms/yrseventh lowest of 39, six tied39 high-draw gas tankless sets
UEFRinnai (CX199I) REU-NB3237FFC-US0.980.96highest of 39, six tied39 high-draw gas tankless sets
Gas inputRinnai (CX199I) REU-NB3237FFC-US199,000 Btu/h180,000 Btu/hhighest of 40, 13 tied40 gas tankless sets

Model numbers

The line covers 8 model numbers, first certified 2024-01-19 and most recently 2024-01-25.

Model numberBrandRating setVentFuelMin flowCertified
(CX160I) REU-NB2530FFC-USRinnai(CX160I) REU-NB2530FFC-USPower Direct Ventnatural gas or propane0.10 gal/min2024-01-25
(CXP160I) REU-NBP2530FFC-USRinnai(CX160I) REU-NB2530FFC-USPower Direct Ventnatural gas or propane0.10 gal/min2024-01-25
(RX160I) REU-NB2530FF-USRinnai(CX160I) REU-NB2530FFC-USPower Direct Ventnatural gas or propane0.10 gal/min2024-01-25
(RXP160I) REU-NBP2530FF-USRinnai(CX160I) REU-NB2530FFC-USPower Direct Ventnatural gas or propane0.10 gal/min2024-01-25
(CX199I) REU-NB3237FFC-USRinnai(CX199I) REU-NB3237FFC-USPower Direct Ventnatural gas or propane0.10 gal/min2024-01-25
(CXP199I) REU-NBP3237FFC-USRinnai(CX199I) REU-NB3237FFC-USPower Direct Ventnatural gas or propane0.10 gal/min2024-01-25
(RX199I) REU-NB3237FF-USRinnai(CX199I) REU-NB3237FFC-USPower Direct Ventnatural gas or propane0.10 gal/min2024-01-19
(RXP199I) REU-NBP3237FF-USRinnai(CX199I) REU-NB3237FFC-USPower Direct Ventnatural gas or propane0.10 gal/min2024-01-25

Nearest certified alternatives

Rating setMax flowUEFGas input
Rheem ECOHS160INcompared with Rinnai (CX160I) REU-NB2530FFC-US±0.0 gal/min−0.01−3,000 Btu/h
Vesta VTS-150compared with Rinnai (CX160I) REU-NB2530FFC-US±0.0 gal/min−0.01−10,000 Btu/h
Noritz EZ71DV (GQ-C2661WX-FF US)compared with Rinnai (CX160I) REU-NB2530FFC-US+0.1 gal/min+0.01same Btu/h
Noritz NRCR92DV (GQ-C2661WXQ-FF US)compared with Rinnai (CX160I) REU-NB2530FFC-US+0.1 gal/min+0.01+5,000 Btu/h
Noritz EZ111DV (GQ-C3261WX-FF US)compared with Rinnai (CX199I) REU-NB3237FFC-US−0.3 gal/min±0.00same Btu/h

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