# How Old Is My Unit

> Serial number age decoder for HVAC, water heaters, boilers, generators and appliances

Decodes the manufacture date in equipment serial numbers for 219 brands (126 with sourced formats, 218 rules, 161 machine-decodable). Every rule carries an era, a pattern, the decode rule in plain English, transcribed letter tables, a worked example, an ambiguity note, a status (VERIFIED / PARTIAL / UNSOURCED) and sources. Each brand page links the manufacturer's official lookup as the authority.

## Key facts

- Carrier (1980 to present): Example: serial 4006A17330 decodes to week 40 of 2006.
- Carrier (1980 to 1989): Example: serial 850304091 decodes to March 1985.
- Carrier (1969 to 1979): Example: serial A167890 decodes to January 1971.
- Carrier (1960 to 1979): Example: serial 46U152456 decodes to week 46 of 1967.
- Trane (2010 to present): Example: serial 130313596L decodes to week 3 of 2013.
- Trane (2002 to 2009): Example: serial 91531S41F decodes to week 15 of 2009.
- Trane (1983 to 2001): Example: serial F23456789 decodes to week 23 of 1991.
- Lennox (1973 to present): Example: serial 5899L17212 decodes to November 1999.
- Lennox (before 1972): Example: serial 6512 decodes to December 1965.
- Goodman (1990 to 2013): Example: serial 5FU5472618P decodes to June 2008.
- Rheem (era not stated): Example: serial W291013412 decodes to week 29 of 2010.
- Rheem (era not stated): Example: serial 7351 M2806 16735 decodes to week 28 of 2006.
- Rheem (era not stated): Example: serial 0804B10488 decodes to August 2004.
- York (2004 to present): Example: serial W0K5896070 decodes to September 2005.
- York (1971 to 2004): Example: serial WAKM011379 decodes to 1980 or 2001 (January).
- A.O. Smith (2008 to present): Example: serial 1210A002243 decodes to week 10 of 2012.
- A.O. Smith (before 2010): Example: serial E07A135491 decodes to May 2007.
- A.O. Smith (before 2008): Example: serial AF04A093001 decodes to June 2004.
- A.O. Smith (1970 to 1979): Example: serial A20-H-78-015482 decodes to August 1978.
- Bradford White (1984 to present): Example: serial DG6322957 decodes to 1987 or 2007 (July).
- Navien (era not stated): Example: serial 9545J1152752044 decodes to May 2011.
- Whirlpool (1990 to present): Example: serial MX040676 decodes to week 4 of 1990 or 2020.
- Bryant (1980 to 1984): Example: serial W4D14008 decodes to September 1984.
- Bryant (1980 to 1984): Example: serial 4WD14008 decodes to September 1984.
- ICP (1990 to present): Example: serial E072514528 decodes to week 25 of 2007.
- ICP (1990 to 1999): Example: serial 9414B39332 decodes to week 14 of 1994.
- ICP (2000 to present): Example: serial 4102G12345 decodes to week 41 of 2002.
- ICP (1980 to 1989): Example: serial H55116328 decodes to week 51 of 1985.
- ICP (1980 to 1993): Example: serial 30512345 decodes to week 5 of 1983 or 1993.
- Heil (before 1979): Example: serial 297448 decodes to 1952 or 1962 or 1972.
- Kenmore HVAC (era not stated): Example: serial 320100007S decodes to week 32 of 2001.
- Ameristar (2010 to present): Example: serial 16323AP91G decodes to week 32 of 2016.
- Allied Air (era not stated): Example: serial 4601J19567 decodes to September 2001.
- Allied Air (era not stated): Example: serial 4140720328 decodes to week 28 of 2003.
- Armstrong Air (1978 to 1992): Example: serial A14019ELA decodes to May 1990.
- Allied Air (1970 to 1977): Example: serial 15A67JA098 decodes to January 1976.
- WeatherKing (before 1989): Example: serial 28607168189 decodes to July 1986.
- Richmond (era not stated): Example: serial 1204D01234 decodes to December 2004.
- Coleman (1992 to 2004): Example: serial 990697368 decodes to June 1999.
- Coleman (before 1991): Example: serial 0188123456 decodes to January 1988.
- Luxaire (era not stated): Example: serial 97104119 decodes to October 1997.
- Champion Cooler (Essick Air) (era not stated): Example: serial E07141664 decodes to May 2007.
- Amana HVAC (era not stated): Example: serial 96-90391 decodes to 1996.
- Amana HVAC (era not stated): Example: serial 040590391 decodes to May 2004.
- Janitrol (before 1985): Example: serial 0759F5616 decodes to July 1959.
- Nordyne (era not stated): Example: serial GBB030708229 decodes to July 2003.
- Nordyne (era not stated): Example: serial MN3D102 F3891 4228 decodes to week 38 of 1991.
- Nordyne (era not stated): Example: serial G6R9905-05028 decodes to May 1999.
- Mitsubishi Electric (era not stated): Example: serial 89D00488D decodes to 1958 or 1968 or 1978 or 1988 or 1998 or 2008 or 2018 (September).
- Mitsubishi Electric (era not stated): Example: serial 8001637 T decodes to 1958 or 1968 or 1978 or 1988 or 1998 or 2008 or 2018.
- Daikin (2012 to present): Example: serial 1602393269 decodes to February 2016.
- Daikin (era not stated): Example: serial FBOU0905048200 decodes to May 2009.
- Daikin (1977 to 1989): Example: serial 049270032 decodes to week 27 of 1979 or 1989.
- Daikin (1995 to 1999): Example: serial 55A1234501 decodes to January 1995.
- Daikin (1971 to 1994): Example: serial 5PB1234503 decodes to February 1984.
- Daikin (1988 to present): Example: serial R881212345 decodes to week 12 of 1988.
- Daikin (1974 to 1988): Example: serial 1230456789M151234 decodes to week 15 of 1985.
- Daikin (1964 to 1970): Example: serial YA123456 decodes to January 1969.
- LG (2000 to present): Example: serial 207KRMK0Y171 decodes to 2002 or 2012 or 2022 (July).
- LG (before 2012): Example: serial EQ11220013150001 decodes to March 2001.
- Samsung (2001 to present): Example: serial J0V07DDC400695M decodes to April 2012.
- Gree (era not stated): Example: serial 2020.05 decodes to May 2020.
- Midea (era not stated): Example: serial V180543529 decodes to week 5 of 2018.
- MrCool (2010 to present): Example: serial 2402135890267230130069 decodes to 2016 or 2026 (July).
- Bard (1980 to present): Example: serial 000F950926066-1 decodes to May 1995.
- Bard (1980 to 1980): Example: serial 123DA45678 decodes to April 1980.
- Bard (1962 to 1980): Example: serial 28193MT decodes to October 1978.
- Bard (era not stated): Example: serial 36284 M83 decodes to October 1983.
- Bard (era not stated): Example: serial 940128116 decodes to 1994.
- Comfort-Aire (era not stated): Example: serial RSF150300183 decodes to March 2015.
- Comfort-Aire (era not stated): Example: serial EB5D302F320107830 decodes to week 32 of 2001.
- Comfort-Aire (era not stated): Example: serial 0804237539 decodes to April 2008.
- Comfort-Aire (era not stated): Example: serial R0424070098 decodes to week 24 of 2004.
- AAON (2000 to present): Example: serial 200108AKG26241 decodes to August 2001.
- AAON (1990 to 1999): Example: serial 97JKGK153 decodes to September 1997.
- AAON (before 1999): Example: serial AKEC08701 decodes to January 1987.
- ClimateMaster (1998 to present): Example: serial K111300076 decodes to week 11 of 2007.
- ClimateMaster (before 1997): Example: serial 92J010915 decodes to September 1992.
- WaterFurnace (2012 to present): Example: serial 180100228 decodes to October 2018.
- WaterFurnace (1985 to 2012): Example: serial UJ1087 decodes to September 2004.
- WaterFurnace (before 1984): Example: serial D8367019 decodes to April 1983.
- Williams (1984 to 2004): Example: serial 13 AD decodes to January 1987.
- GE Zoneline (PTAC) (1944 to present): Example: serial ZTN730A100AC decodes to 2010 or 1998 or 1986 or 1974 or 1960 (December).
- General Electric (legacy central HVAC, pre-1982) (1960 to 1989): Example: serial 359952809 decodes to week 9 of 1968 or 1978 or 1988.
- General Electric (legacy central HVAC, pre-1982) (1965 to 1985): Example: serial HM409295 decodes to August 1976.
- Amana PTAC (1997 to present): Example: serial 0109145052 decodes to September 2001.
- State (before 2010): Example: serial H765662231 decodes to August 1976.
- State (before 2004): Example: serial AF04A093001 decodes to June 2004.
- American Water Heater (2008 to present): Example: serial 1924115263020 decodes to week 24 of 2019.
- American Water Heater (before 2007): Example: serial 05035 35368 decodes to March 2005.
- Reliance (before 2010): Example: serial L92441351 decodes to August 1992.
- Reliance (before 2010): Example: serial C91A136750 decodes to December 1991.
- Reliance (2008 to present): Example: serial 1211A018632 decodes to week 11 of 2012.
- Whirlpool water heaters (era not stated): Example: serial 1104T403904 decodes to week 4 of 2011.
- Kenmore water heaters (before 2010): Example: serial A03307353 decodes to January 2003.
- Kenmore water heaters (2008 to present): Example: serial 1210A002243 decodes to week 10 of 2012.
- U.S. Craftmaster (era not stated): Example: serial 0020118002 decodes to week 20 of 2000.
- GSW (2008 to present): Example: serial U1117 F700633 decodes to week 17 of 2011.
- John Wood (before 2007): Example: serial U0106413635 decodes to June 2001.
- John Wood (2008 to present): Example: serial U0928413635 decodes to week 28 of 2009.
- John Wood (before 2005): Example: serial 137945-7503 decodes to March 1975.
- John Wood (before 2005): Example: serial 8711-127684 decodes to November 1987.
- Lochinvar (1979 to 2011): Example: serial KJ-1000130 decodes to September 1993.
- Lochinvar (2011 to present): Example: serial 1142N012345 decodes to week 42 of 2011.
- Lochinvar (1978 to present): Example: serial J-930001 decodes to September 1993.
- Lochinvar (1978 to present): Example: serial A07H00123456 decodes to January 2007.
- Lochinvar (1965 to 1986): Example: serial M78013 decodes to December 1978.
- Lochinvar (1968 to 1981): Example: serial 5Y013 decodes to May 1978.
- Lochinvar (1978 to 2010): Example: serial 1234569708 decodes to August 1997.
- Lochinvar (1984 to present): Example: serial 85041234 decodes to April 1985.
- Takagi (2010 to present): Example: serial 1544E000453 decodes to week 44 of 2015.
- Ruud water heaters (era not stated): Example: serial RU 0904B21710 decodes to September 2004.
- Ruud water heaters (era not stated): Example: serial RHLN 0106534307 decodes to January 2006.
- Ruud water heaters (2010 to present): Example: serial A141511869 decodes to week 14 of 2015.
- Ruud water heaters (era not stated): Example: serial D1114A441408265A decodes to November 2014.
- Ruud water heaters (era not stated): Example: serial 05.05-000021 decodes to May 2005.
- GE/GeoSpring (era not stated): Example: serial 1108903259 decodes to November 2008.
- HTP (1994 to 2011): Example: serial I21M28666 decodes to September 2006.
- HTP (2011 to 2021): Example: serial 112116E2054485 decodes to November 2016.
- HTP (2021 to present): Example: serial 3251200U4220450000188 decodes to day 45 of 2022.
- Ariston (era not stated): Example: serial J21-6869 decodes to September 2021.
- Noritz (era not stated): Example: serial 2005.06-004472 decodes to June 2005.
- Buderus (era not stated): Example: serial 63036333-00-7080-3241 decodes to day 80 of 1957 or 1967 or 1977 or 1987 or 1997 or 2007 or 2017.
- Buderus (era not stated): Example: serial 253000-08065-00040-77470007354 decodes to day 65 of 2008.
- Peerless (2000 to present): Example: serial 339090-200012 decodes to December 2000.
- Peerless (1984 to 1999): Example: serial 123456-1284 decodes to December 1984.
- Crown (2004 to present): Example: serial AI decodes to January 2012.
- Crown (era not stated): Example: serial 98023429 decodes to 1998.
- Utica (2005 to present): Example: serial 160500150 decodes to week 16 of 2005.
- Utica (1979 to 2001): Example: serial HT11826 decodes to August 1996.
- IBC (era not stated): Example: serial 051577-1410k00314 decodes to October 2014.
- Laars (era not stated): Example: serial C00B01803 decodes to March 2000.
- Laars (before 1999): Example: serial 8408375 decodes to 1984.
- Energy Kinetics (era not stated): Example: serial 299078847 decodes to July 1999.
- Energy Kinetics (era not stated): Example: serial F 10608063248 decodes to August 2006.
- Briggs & Stratton (1965 to present): Example: serial 99011556 decodes to January 1999.
- Whirlpool (1990 to present): Example: serial MX06404786 decodes to week 6 of 1990 or 2020.
- Maytag (1966 to 2010): Example: serial 12772864EL decodes to 1980 or 2004 (June).
- Amana (before 2002): Example: serial 9206152586 decodes to week 6 of 1992.
- GE Appliances (1977 to present): Example: serial LR821547C decodes to 2020 or 2008 or 1996 or 1984 (June).
- Electrolux (1986 to present): Example: serial LA81503430 decodes to week 15 of 1988 or 1998 or 2008 or 2018.
- Speed Queen (1998 to present): Example: serial 1107008829 decodes to July 2011.
- Speed Queen (Alliance European-built) (2009 to present): Example: serial 520I000001DK decodes to May 2015.
- Bertazzoni (era not stated): Example: serial 4220 decodes to week 42 of 2020.

## Pages

- https://howoldismyunit.com/
- https://howoldismyunit.com/brand/
- https://howoldismyunit.com/category/
- https://howoldismyunit.com/guide/
- https://howoldismyunit.com/about/
- https://howoldismyunit.com/data/

Every page (1,150 URLs): https://howoldismyunit.com/sitemap.xml

## Data downloads

- https://howoldismyunit.com/data/brands.csv - one row per brand: parent, categories, rule count, official lookup URL
- https://howoldismyunit.com/data/formats.csv - one row per serial format era: pattern, example, decode rules, status, sources
- https://howoldismyunit.com/data/lookups.csv - official warranty / serial lookup URLs with verification status

Sources are cited per rule; see https://howoldismyunit.com/about/