RINNAI REP199E (REU-VEP2730WD-US)

The 209 therms figure is not printed in the registry; this site computed it. It combines two inputs. The first is the model's UEF, the ratio of hot water delivered to energy used, listed at 0.81. The second is the DOE test's daily hot-water draw for the high draw pattern. The registry values come from DOE CCD, retrieved 2026-09-19. The result holds at the federal test's draw, not at a measured household draw. A home that uses more hot water than the test assumes will burn more gas. How large that gap is for a given home is not available in the data. The page on how this site calculates annual energy and cost lists each input and its source.

Its class is the 397 models registered as a gas tankless unit at the high draw pattern. The class median is 182 therms, and this model sits 27 therms above it at the same test draw. It ranks 323rd for lowest energy use out of 397, which places it in the highest quarter of its class for energy use. The high draw pattern stands for a larger household, or one where showers and laundry overlap. That is the use the rating describes. The registry lists a maximum flow rate in gallons per minute of 4.9. Whether that covers a home's fixtures running together depends on their flow rates, which the data does not include. The selector by fuel, space and size filters by these factors.

For a reader whose priority is lower gas use at the high draw pattern, the 323rd rank noted above is the relevant figure. The tool to find a same-class replacement by model number lists other models in the same class for comparison. Running cost is not written in this text. It depends on your state's average residential gas price. The page applies that price to 209 therms using your ZIP, through the cost calculator for your own ZIP. The installed price range appears in its own block with its source and date. It is a modeled installed-cost range, not a quote, and this text does not restate it.