Mor-Flo Water Heater Age Tool

Mor-Flo water heaters carry a legacy American brand name with origins tracing to 1915 and the founding of The Hotstream Heater Company in Cleveland, Ohio, which emerged from the earlier American Water Heater Company and American Heater Corporation. The Mor-Flo name became formally established when Hotstream merged with the Buckeye Water Heater Company in 1961 to form Mor-Flo Industries, Inc. Over the following decades, Mor-Flo grew into one of the largest domestic water heater producers in the United States through a combination of organic growth and strategic acquisitions, most notably the 1972 purchase of California-based American Appliance Mfg. Corp., which created the Mor-Flo/American brand family. The company also gained historical significance in the industry as the developer of the Flame Guard flammable vapor ignition resistant (FVIR) safety system, introduced commercially around 2000 and later mandated on all residential gas water heaters in 2003.

Mor-Flo produced a broad range of residential and light commercial gas and electric tank water heaters under both the Mor-Flo and Mor-Flo/American names, serving both builder and replacement markets through wholesale plumbing distributors. In 1993, the Australian conglomerate Southcorp Limited acquired Mor-Flo Industries, and by 1997 the various Mor-Flo entities were merged to form American Water Heater Company. American Water Heater Company was subsequently acquired by GSW Limited in 2002, which was itself purchased by A.O. Smith Corporation in 2006. As a result, Mor-Flo branded water heaters are now part of the A.O. Smith family of brands, though new production under the Mor-Flo name has largely been phased out in favor of the American Water Heater brand.

Mor-Flo serial numbers follow several different formats depending on the era of production. The most common modern formats place the two-digit year in the first or second position followed by a two-digit week number — either at the start of an all-numeric serial (Style 1) or after a single letter prefix (Styles 2 and 5). Older units from the 1970s and 1980s sometimes used sequential serial numbers with no date encoding; for these, a separate warranty code printed on the data plate provides the manufacture date in either a letter-plus-year (Style 3) or four-digit year-week (Style 4) format. Entering the warranty code into the tool instead of the serial number will allow the date to be retrieved for these older units.