ARISTON PV50TLN*

The registry lists this model's UEF, the ratio of hot water delivered to energy used, as 0.7. This site computed 242 therms of natural gas a year from that UEF and the daily hot-water draw the DOE test uses for the high draw pattern. The source is DOE CCD, retrieved 2026-09-19. The figure applies only at that draw. The class is the 414 models registered as a gas tank at the high draw pattern, and its median is 260 therms. This model sits 18 therms below that median, at 90th lowest energy use of 414. That places it in the lowest quarter of its class. The steps behind the annual figure are set out under how the annual cost is calculated.

The high draw pattern describes a larger household, or one where showers and laundry overlap. For this model the registry lists a first hour rating, the gallons of hot water available in the first hour from a full tank, of 81 gallons. Its rated volume is 48 gallons. The energy figure fits a reader whose daily use matches the federal test's draw. It does not describe a household whose use is far from that draw, and no figure for another draw pattern is available here. Actual use in a particular home is not measured in the registry data. To compare units by fuel, space and size, use the water heater selector.

The running cost is not stated in this text. It depends on the state average residential gas price, and 242 therms at the high draw pattern is the quantity that price applies to. The cost calculator for your own ZIP applies that price to this model's figure. A modeled cost is not a bill, and a household paying a rate different from the state average will see a different result. The modeled installed-cost range appears in its own block on this page, with its source and date, and is not restated here. To look for a same-class unit, you can find a replacement by model number starting from PV50TLN*. The 18 therms gap to the class median of 260 therms is a difference in energy, not in price.