Rinnai CX199I REU-NB3237FFC-US is a gas tankless water heater from Rinnai rated 5.8 GPM at a 0.98 UEF — 173 therms/yr certified use, 199k BTU/h input.
MSRP: $2,085
Efficiency
Uniform Energy Factor (UEF)
0.98
Annual gas use (natural gas)
173 therms/yr
Recovery efficiency
99 %
Annual propane use
189.07 gal/yr
General
Fuel
Natural Gas, Propane
Capacity
Max flow rate
5.8 GPM
Draw pattern
High
Minimum activation flow
0.1 GPM
Performance
Gas input rate
199 kBTU/h
Installation
Max current draw
4 A
Vent type
Power Direct Vent
Vent size
2
Smart features
Smart / connected capable
No
Dimensions
Height
25.8 in
Diameter
11.4 in
Width
18.5 in
Depth
11.4 in
Certification
ENERGY STAR certified
Yes
Real flow rate by climate
A tankless heater's usable flow depends on how far it must raise incoming water
temperature. Sustained hot-water flow of the Rinnai CX199I REU-NB3237FFC-US at common temperature
rises (a typical shower uses about 2 GPM of mixed water):
The Rinnai CX199I REU-NB3237FFC-US is certified hardware that Rinnai and its partner brands
publish under 4 names. The same specifications apply to every
variant:
Is the Rinnai CX199I REU-NB3237FFC-US ENERGY STAR certified?
Yes, the Rinnai CX199I REU-NB3237FFC-US holds a current ENERGY STAR certification for water heating efficiency (UEF 0.98).
How much does the Rinnai CX199I REU-NB3237FFC-US cost to run per year?
About $251 per year at national average energy rates, based on its certified annual energy use under the DOE test draw pattern. Your rate and usage change this figure.
What venting does the Rinnai CX199I REU-NB3237FFC-US use?
The Rinnai CX199I REU-NB3237FFC-US uses Power Direct Vent venting with 2 in vent connections. Matching the existing vent type is usually the cheapest replacement path.
Is the Rinnai CX199I REU-NB3237FFC-US a smart water heater?
No, the Rinnai CX199I REU-NB3237FFC-US is not connected-capable — it has no app connectivity or demand-response support.
