RELIANCE WATER HEATERS GCF-50 1**

The 245 therms figure is calculated by this site. The registry does not publish 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. For this model the UEF is 0.69, from the DOE CCD, retrieved 2026-09-19. The comparison covers the 414 models registered as a gas tank at the high draw pattern. In that class, this unit ranks 130th lowest in energy use. That puts it in the second-lowest quarter of its class. The figure applies only at the test's daily draw. The registry gives no energy use for a home that draws more or less hot water. The steps are set out in how the annual energy and cost are calculated.

The high draw pattern stands for a larger household, or one where showers and laundry overlap. This model lists a first hour rating, the gallons of hot water available in the first hour from a full tank, of 84 gallons. Its rated volume is 48 gallons. These figures describe the test conditions behind the 245 therms value. The test does not describe a smaller household that draws less hot water. The registry gives no energy figure for this model at another draw pattern, so that value is not available here. To compare this unit with others registered at the same draw pattern, use the same-class replacement search by model number.

This text does not state the running cost. It depends on the average residential gas price in the reader's state, so the page calculates it from the reader's ZIP. The 15 therms gap below the 260 therms class median is a difference in energy. What that gap costs each year also depends on the reader's rate. Enter a ZIP in the running-cost calculator for your own ZIP to see the figure for this model. The installed price range is shown in its own block, with its source and date. It is a modeled range for installed cost, not a quote. The running cost uses the same 245 therms at the high draw pattern given above.