Noritz NCC199CDV (GQ-C3261WZ-FF US)

This site calculated the 173 therms figure; the registry does not publish it. The calculation starts from the registry's UEF, the ratio of hot water delivered to energy used. For this model, the UEF is 0.98. The calculation then applies the daily hot-water draw that DOE's test sets for the high draw pattern. The source is DOE's Compliance Certification Database (CCD), retrieved 2026-09-19. The figure holds only at that test draw. A home that draws more hot water each day will use more gas than 173 therms, and a home that draws less will use less. The registry does not give this model's energy use at the other draw patterns, so that value is not available here. Each step is set out on the page explaining how the annual energy and cost figures are calculated.

In plain terms, the high draw pattern describes a larger household, or one where showers and laundry overlap. The registry lists this unit's maximum flow rate in gallons per minute as 5.5. The registry data used here does not state the temperature rise behind that rating, so that detail is not available. A home that needs more than 5.5 of hot water at one time asks for more than the listed rating. For a smaller home with lower daily use, the 173 therms figure does not describe its own consumption, since that figure was calculated at the high draw pattern. If you are comparing units by fuel, space and size rather than checking this one, the water heater selector by fuel, space and size covers that comparison.

Within the class described in the first paragraph, the registry data ranks this model 1st lowest in energy use of 397. That places it in the lowest quarter of the class for energy use. The 9 therms gap to the class median is a difference in gas use, not in cost. The running cost depends on your state's average residential gas price, so it is not stated in this text. The page calculates it from your ZIP with the running cost calculator for your own ZIP. The installed price appears in its own block, with its source and date. It is a modeled range, not a quote. To check units in the same class by model number, use the same-class replacement finder.