TAKAGI T-H3-DV-N 1**

The 182 therms figure comes from this site's own calculation. The registry does not publish it. The calculation combines the registry's UEF, the ratio of hot water delivered to energy used, with the DOE test's daily hot-water draw for the high draw pattern. This model's UEF is 0.93. The result holds only at that federal test draw. A household that draws more or less hot water than the test will use more or less gas than 182 therms. The registry data comes from the DOE CCD and was retrieved on 2026-09-19. The page on how the annual energy and cost figures are calculated sets out the same inputs step by step.

This model is compared with the 397 models registered as a gas tankless unit at the high draw pattern. Its rank is 183rd lowest energy use. Its 182 therms matches the class median of 182 therms, a difference of 0 therms. That puts it in the second-lowest quarter of its class for energy use. The high draw pattern describes a larger household, or one where showers and laundry overlap. The figure was measured for a home like that. A smaller household with lighter hot-water use is outside that test condition, so 182 therms does not describe its use. The registry lists a maximum flow rate in gallons per minute of 5.8 for this model. This data does not show how many fixtures that flow supports at once. To check other units in the same class, find a same-class replacement by model number.

This text does not give the running cost of 182 therms a year. That cost depends on your state's average residential natural gas price. The page works it out from your ZIP and does not use a single national estimate. Enter your ZIP in the water heater cost calculator for your ZIP to apply your own rate to this model's 182 therms. At the same rate, the difference in gas cost from a class-median model depends on the 0 therms gap in annual use. The installed-cost range appears in its own block on this page, with its own source and date. That range is modeled from data. It is not a quote from an installer.