TAKAGI T-H3M-DV-N 1**

The figure of 123 therms was computed by this site, not by the registry. The registry lists a UEF, the ratio of hot water delivered to energy used, of 0.9. This site combined it with the federal test's daily hot-water draw for the medium draw pattern. The source is DOE CCD, retrieved 2026-09-19. The medium pattern represents a typical household on a busy morning. This model sits 12 therms below the class median of 135 therms. That places it 10th lowest of 80 gas tankless models, in the lowest quarter of its class for energy use. The comparison covers only gas tankless units registered at the medium draw pattern.

This figure suits a reader who wants to check the unit against other gas tankless models at the medium draw pattern. It does not describe a household whose daily use differs from the federal test's daily hot-water draw. This page has no energy figure for other draw patterns. The maximum flow rate in gallons per minute is 3.3. That rate limits how much hot water the unit can deliver at once and says nothing about yearly energy. Real-world water temperature, climate and usage are not available here, so actual gas use may differ from 123 therms. To compare other fuels, spaces or sizes, use the water heater selector, or find a same-class replacement by model number.

The running cost is not stated in the text because it depends on your state's average residential gas price. Multiply 123 therms by your local rate to get a yearly figure. The cost calculator does this from your ZIP. The methodology page explains how the annual cost is calculated. The gap of 12 therms against the class median of 135 therms is the amount to price at your own rate. Any cost holds only for the medium draw pattern, natural gas and the retrieval date of 2026-09-19. The modeled installed-cost range appears in its own block with its source and date, and this text does not restate it.