Rheem RTG-84XLN-3

This site calculated the 206 therms figure; the registry does not publish it. The calculation uses the registry's UEF, the ratio of hot water delivered to energy used, which is 0.82 for this model. It also uses the DOE test's daily hot-water draw for the high pattern. The high draw pattern represents a larger household, or one where showers and laundry overlap. The figure applies only at that test draw. A household that uses more hot water than the test assumes will burn more gas, and one that uses less will burn less. The registry values come from the DOE CCD, retrieved 2026-09-19. The page on how the annual cost is calculated sets out each step from UEF to yearly use.

The comparison group is the 397 models registered as gas tankless units at the high draw pattern. At 24 therms above the class median of 182 therms, this model ranks 229th, which places it in the second-highest quarter of its class for energy use. This means more than half of the registered models in its class use less gas at the same test draw. It fits a household whose daily use matches the high pattern. It is not the match for a reader whose goal is the lowest gas use in this class. Its maximum flow rate in gallons per minute is 4.4. That is the registry's measure of how much hot water it delivers at once. To compare it with other models in the same class, use find a same-class replacement by model number.

This text gives no running cost. The cost of 206 therms a year depends on the reader's state average residential gas price. The page calculates that cost from the reader's ZIP rather than stating one fixed figure for every state. For the same reason, the cost of the 24 therms gap to the class median is higher where gas is priced higher and lower where it is priced lower. To see the result for one address, enter it in the cost calculator on your own ZIP. The installed-cost range appears in its own block on this page, with its source and date. It is a modeled range, not a quote. What this unit will add to a specific gas bill stays unknown until a rate is entered.