ARISTON PV40TLN*

The figure of 242 therms of natural gas comes from this site, not from the registry. It starts from the registry's UEF, the ratio of hot water delivered to energy used. It then applies the daily hot-water draw that DOE's test sets for the high draw pattern. The registry gives a UEF of 0.7 for the PV40TLN*. The source is the DOE CCD, retrieved 2026-09-19. Because the figure uses the test's standard draw, it does not predict the use of any one home. Among gas tank models at the high draw pattern, this model has the 90th lowest energy use of 414. That places it in the lowest quarter of its class.

The energy figure belongs to the high draw pattern, meaning a larger household, or one where showers and laundry overlap. The registry lists a first hour rating, the gallons of hot water available in the first hour from a full tank, of 78 gallons. The rated volume is 38 gallons. Those two values describe supply, while the 242 therms describes energy use at the test draw. The data does not say whether this supply meets a given household's peak hour. Energy use at other draw patterns is not available on this page. To compare options by fuel, space and size, use the water heater selector. To look up a same-class unit, use the replacement finder by model number.

The running cost is not stated in the text. It depends on the state average residential gas price, so the page computes it from your ZIP. The calculation applies your local gas price to the 242 therms at the test draw. The 18 therms difference from the class median of 260 therms becomes a cost difference only at your own rate. Use the cost calculator on your own ZIP for that result, and read how the annual cost is calculated for the method. The result is a calculation at the test draw, not a measured bill. The installed price range appears in its own block, as a modeled range and not a quote.