RELIANCE WATER HEATERS T-H3J-OS-N 1**

This site calculated the 178 therms figure; the registry does not state it. It 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 0.95, from DOE CCD data retrieved 2026-09-19. The class median of 182 therms comes from the 397 models registered as a gas tankless unit at the high draw pattern. The gap of 4 therms a year holds only at the federal test's daily draw. A household that draws more or less hot water than the test will use a different amount of gas. The calculation steps are set out in how the annual cost is calculated.

The high draw pattern describes a larger household, or one where showers and laundry overlap. For a home like that, the 178 therms test figure is the relevant one. The registered maximum flow rate in gallons per minute is 4.7. The registry data does not say whether that flow covers several fixtures running at once. A smaller household drawing less hot water will not match the test figure, and this data does not show by how much. To compare other units by fuel, space and size, use the water heater selector. To match a model in the same class, find a same-class replacement by model number.

This text does not state the running cost. It depends on the average residential natural gas price in the reader's state, so the page calculates it from the reader's ZIP. At 178 therms a year, the cost follows that local gas rate. The 4 therms gap to the class median follows the same rate. To run the figure on your own rate, use the cost calculator for your own ZIP. The installed-cost range shown elsewhere on this page is a modeled range with its own source and date, not a quote. The rank of 45th of 397 refers to energy use only, not to cost.