Water Heater Age
Updated: Dec 5, 2022

Often if agents look at the serial plate of main systems, and don't see the age clearly labeled on them, they will leave it to home inspectors to determine. That's not necessary, as you'll see below with a quick reference guide to some of the most common water heaters and a link to more water heater information. For brevity & what's most important, I'm only focusing on the year of manufacture. See the hyperlinks for additional details on the week/month/other information.
Disclosure on Limited Accuracy
Keep in mind that I have seen where following the online charts can lead you in the wrong direction before. I find them to be >95% accurate. Click on the hyperlinks for higher level of accuracy, but if 2 charts vary, look for more charts. It's best to look at more than one source including but not limited to the manufacturer & a home inspector, in addition to the below chart, for the highest level of accuracy. In the event that you ever see inaccurate information on this list, please let me know.
Sources are hyperlinked on each row. For a more comprehensive list, go to Building-Center.org's list here. I found their lists to be more accurate/user-friendly than others, though you'll have to do more digging than the guide below since they don't publish a quick reference chart like this one.
manufacturer | which serial #s for age (focus on year; "numerical digits" excludes alphabetical) | Style Patterns (yr in blue) | Lettering system (if applicable to yr) | |
---|---|---|---|---|
1st 2 yr | Style 1: 05035 35368 Style 2: 1924115263020 | | | |
1st 2 numerical digits = yr | Style 1a: 1210A002243 Style 1b: S1318 F000046 Style 1c: 1836111786352 Style 2: AF04A093001 Style 3: GG03-1495366-S29 Style 4: E07A135491 | | | |
DG6322957 OA822685 | A: 1984 or 2004 B. 1985 or 2005 C. 1986 or 2006 D. 1987 or 2007 E. 1988 or 2008 F. 1989 or 2009 G. 1990 or 2010 H. 1991 or 2011 J. 1992 or 2012 K. 1993 or 2013 L. 1994 or 2014 M. 1995 or 2015 N. 1996 or 2016 OA. 1997 P. 1997 or 2017 S. 1998 or 2018 T. 1999 or 2019 W. 2000 or 2020 X. 2001 or 2021 Y. 2002 or 2022 Z. 2003 or 2023 |