Mor-Flo® Water age

How to determine the date of production/manufacture or age of Mor-Flo^® brand Water Heater Systems.

Water heaters in general have an average estimated useful service life of 10-12 years, though water quality, routine upkeep/maintenance, and location of the water heater will all play critical roles in the longevity of these systems.

Parent Company: A.O. Smith

Subsidiaries or related brands: Mor-Flo | Mor-Flo/American | American | American Appliance Mfg. Corp. |

The date of production/manufacture or age of Mor-Flo® brand Water Heater equipment can be determined from the serial number located on the rating data plate.

Example serial number styles/formats found:

→Style 1: 043812019

→Style 2: J861425155

→Style 3: A201970 (L-75 warranty code listed separately)

→Style 4: A2363113 (8214 warranty code listed separately)

→Style 5: C 86 03 05922 A

Legend: Year is RED; Month is GREEN; Week is BLUE

→Style 1: 043812019

Year of manufacture can be determined by using the 1^st & 2^nd digits of the serial number

Week of manufacture can be determined by using the 3^rd & 4^th digits of the serial number

→Style 2: J861425155

Year of manufacture can be determined by using the 1^st & 2^nd digits of the serial number

Week of manufacture can be determined by using the 3^rd & 4^th digits of the serial number

→Style 3: A201970 (L-75 warranty code listed separately)

This style uses sequential serial numbers which do not reference the manufacture date. The warranty code listed separately must be used to determine the manufacture date.

Year of manufacture can be determined by using the 1^st & 2^nd digits of the warranty code

Month of manufacture can be determined by using the 1^st letter of the warranty code (A-L without skipping letters)

→Style 4: A2363113 (8214 warranty code listed separately)

Similar to style 3, this style uses sequential serial numbers which do not reference the manufacture date. The warranty code listed separately must be used to determine the manufacture date.

Year of manufacture can be determined by using the 1^st & 2^nd digits of the warranty code

Week of manufacture can be determined by using the 3^rd & 4^th digits of the warranty code

→Style 4: C 86 03 05922 A

Year of manufacture can be determined by using the 1^st & 2^nd digits of the serial number (after first letter)

Mor-Flo^® History¹

1915 - The Hotstream Heater Company founded/incorporated in Cleveland, OH. Presumed to be the merger between American Water Heater Company and American Heater Corporation as documented by a U.S. Patent application dated March 12, 1937.
1937 - "American" trademark application submitted by The Hotstream Heater Company. The application for this trademark indicates the name "American" was in use since at least 1912 by American Heater Corporation and American Water Heater Company. Trademark was granted in June of 1937.
1952 - American Appliance Mfg. Corp. founded by Everett S. Todd and Bert Sutton in Santa Monica, California. They began unauthorized but tolerated use of The Hotstream Heater Company (now Mor-Flo) trademarked "American".
1961 - Merger between Mor-Flo Heater Company and The Buckeye Water Heater Company into The Hotstream Heater Company. Name was then changed to Mor-Flo Industries, Inc.
1972 - Mor-Flo acquired California based American Appliance Mfg. Corp. and formed Mor-Flo/American, with American Appliance Mfg. Corp. as a subsidiary.
1979 - A long-running patent infringement legal action began when State Industries brought suit against Mor-Flo and its subsidiary American Appliance Mfg. Corp. for State Industries patent on a method of insulating water heaters with foam.
1989 - The patent infringement suit was finally settled when the Circuit Court Judge found in favor of State Industries. The District Court awarded State Industries lost profits on approximately 40% of Mor-Flo's infringing sales and a royalty of 3% on the remaining 60%. It concluded that Mor-Flo's infringement was not willful and denied enhanced damages and attorney's fees.
1993 - Southcorp Limited (Australian-based company) acquired Mor-Flo Industries.
1995 - Mor-Flo Industries launched American PROLine™
1997 - Mor-Flo Industries merged its companies to form American Water Heater Company
2000 - Introduced the Flame Guard™ system - the first rendering of the flammable vapor ignition resistant (FVIR) safety system. Developed by a Mor-Flo (Southcorp) affiliate Australian company, FVIR safety features became a requirement on all gas-fired water heaters in 2003.
2002 - GSW acquired American Water Heater Group. American was manufacturing water heaters under the U.S. Craftmaster, ENVIRO-TEMP, and American PROline brand names at that time. They had 800 employees in its Johnson City, TN facility.
2006 - A.O. Smith acquires Canadian GSW, Inc. and American Water Heater Company. The addition covers American (US Craftmster, Envirotemp, & American Proline), Whirlpool, GSW, John Woods and their related brands.

_{¹ History excerpts from various industry sources}

Every effort is undertaken to offer you correct and concise information to assist you in determining the age or manufacture date of water heating equipment. Users relying on this information do so at their own risk.

Page last updated: 02/25/2025

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