AMERICAN T-H3M-DV-N 1**

The registry lists a UEF, the ratio of hot water delivered to energy used, of 0.9 for this unit, and a maximum flow rate in gallons per minute of 3.3. This site combines the registry's UEF with the test's daily hot-water draw for the medium draw pattern to reach 123 therms. The registry does not publish that annual figure itself. The condition matters: the figure describes a typical household on a busy morning, and the data was retrieved from DOE CCD on 2026-09-19. A household that draws more or less hot water than the test assumes will use a different amount. The calculation is set out on the methodology page.

Among the 80 models registered as a gas tankless unit at the medium draw pattern, this one has a rank of 10th lowest energy use of 80. That places it in the lowest quarter of its class. Its 123 therms sits 12 therms below the class median of 135 therms. The comparison holds only for models tested at the same draw pattern and fuel. It does not cover other classes, such as tank models or electric units, and their figures are not in this data. It also does not show how the unit behaves in a home whose hot-water use differs from the test. A same-class alternative can be looked up by model number with the replacement finder.

Running cost is not stated in this text because it depends on the state average residential gas price, which differs by reader. The cost calculator applies the price for your ZIP to 123 therms. Because the figure is in therms, a higher gas price raises the cost in direct proportion, and the 12 therms gap to the class median scales with your rate in the same way. The figure suits a household on natural gas whose use is close to the medium draw pattern. It does not apply to a household on another fuel, or to one whose daily use is far from the test's. The maximum flow rate of 3.3 is a separate limit on simultaneous use, and the registry data here does not say how many fixtures that supports. Installed cost is shown in its own block on the page.