Mizudo FDG-CF170

This site calculated the 206 therms figure; the registry does not list it. The calculation uses two things. One is the registry's UEF, the ratio of hot water delivered to energy used. The other is the daily hot-water draw that the DOE test sets for the high draw pattern. For the FDG-CF170, the UEF is 0.82. The result applies only at that test draw. A household that uses more hot water will burn more gas, and one that uses less will burn less. The high draw pattern represents a larger household, or one where showers and laundry overlap. The registry data comes from DOE's Compliance Certification Database, retrieved 2026-09-19. You can see each step in how this site calculates annual energy and running cost.

The FDG-CF170 is compared with the 397 models registered as gas tankless units at the high draw pattern. It uses 24 therms more a year than the class median of 182 therms. It ranks 229th lowest in energy use of 397. That puts it in the second-highest quarter of its class for energy use. So more than half of the class uses less gas at the same test draw. The figure is closest to real use in a household near the high draw pattern. It is less reliable in a home that uses much less hot water than that pattern. The unit's maximum flow rate in gallons per minute is 4.2. To list other models in the same class, use the same-class replacement search by model number.

This text gives no running cost because the cost depends on your state's average residential gas price. The page calculates it from your ZIP by applying that price to the 206 therms used at the high draw pattern. At the same rate, the 182 therms class median shows what the 24 therms gap costs where you live. Any cost figure depends on both conditions: the test draw and your state's rate. The installed price range appears in its own block with its source and date. It is a modeled range, not a quote. To run the figure for another ZIP, use the running cost calculator for your own ZIP.