Westinghouse HW199

This site calculated the 209 therms figure. The registry does not publish it. The calculation uses the registry's UEF, the ratio of hot water delivered to energy used, and the daily hot-water draw in the DOE test for the high draw pattern. The UEF for the HW199 is 0.81. The source is the DOE CCD, retrieved 2026-09-19. The figure is only valid at that test draw. A household that uses more or less hot water each day will use a different amount of gas, and this page does not give that amount. The steps and inputs are listed in how the annual cost is calculated.

The high draw pattern stands for a larger household, or one where showers and laundry overlap. The registered maximum flow rate in gallons per minute for the HW199 is 5. Its class is the 397 models registered as gas tankless units at the high draw pattern. Within that class, its energy use falls in the highest quarter: it ranks 323rd lowest of 397 at the test draw. If you need a lower annual gas figure at the same draw pattern, most registered models in this class use less. To compare it with units in the same class, use the same-class replacement search by model number.

The text of this page does not give a running cost. The cost of 209 therms of natural gas depends on the average residential gas price in your state, so the page calculates it from your ZIP. That same rate sets the cost of the 27 therms gap between this unit and the 182 therms class median. This text does not give a figure for that gap. You can work out both figures with the cost calculator for your own ZIP. The installed price range is shown in its own block, with its source and date. It is a modeled installed-cost range, not a quote.