Electrolex EHW199

The 209 therms figure applies only at the high draw pattern and only to natural gas. This site computed it, not the registry. The inputs are the registry's UEF, the ratio of hot water delivered to energy used, and the test's daily hot-water draw. This model's UEF is 0.81. Among the 397 models registered as a gas tankless unit at this draw pattern, the class median is 182 therms. The Electrolex EHW199 sits 27 therms above it. Its rank is 323rd lowest energy use of 397, which puts it in the highest quarter of its class for energy use. The source is DOE CCD, retrieved 2026-09-19.

The 209 therms figure was set at the high draw pattern, so it speaks to a larger household, or one where showers and laundry overlap. It does not show how the unit performs in a particular home. The registry lists a maximum flow rate in gallons per minute of 5. Whether that covers simultaneous use in one building is not available in this data. The selector by fuel, space and size narrows models by those limits. The unit suits less well a reader whose main aim is low gas use, because its rank of 323rd lowest of 397 and its 27 therms gap above the median point to higher consumption than most of the class. A same-class alternative can be found with the replacement finder by model number, starting from EHW199.

The running cost is not stated in the text, because it depends on the state average residential gas price for the reader's ZIP. The 209 therms figure is the fixed quantity in that calculation, so a different gas price changes the result without changing the therms. The cost calculator on your own ZIP applies the price for you, and how the annual cost is calculated sets out the method. The modeled installed-cost range appears in its own block with its source and date; it is a modeled range, not a quote. A household that uses hot water differently from the high draw pattern will see a different figure from 209 therms, and this page has no value for other patterns.