# Furnace & AC Age Help **URL:** \ **Category:** Inspecting HVAC Systems\ **Created:** [July 19, 2007, 5:00pm UTC](https://forum.nachi.org/t/furnace-ac-age-help/18551 "2007-07-19T17:00:44Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![tpalma](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/tpalma/32/175305_2.png) [@tpalma](https://forum.nachi.org/u/tpalma)\ **Post date:** [July 19, 2007, 5:00pm UTC](https://forum.nachi.org/t/furnace-ac-age-help/18551/1 "2007-07-19T17:00:44Z")
I’m looking to verify the age of a furnace and AC I came across a York Furnace and AC in a townhouse built in 2001. The furnace model P4DNA12N06401A, Serial ECKM061510 My info tells me this was manufactured in 1980. Is this true. AC also a York. Model H1RA024S06D. Serial WNJM004798 I don’t have any info on looking this up. Any help would be appreciated. Tom ---
**Author:** ![bhartley](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/bhartley/32/1448_2.png) [@bhartley](https://forum.nachi.org/u/bhartley)\ **Post date:** [July 19, 2007, 5:36pm UTC](https://forum.nachi.org/t/furnace-ac-age-help/18551/2 "2007-07-19T17:36:57Z")
Tom, Prseton’s Guide, says the York Furnace was built between 2000 & 2005. The AC was built between 1996-2005 ---
**Author:** ![dvalley](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/dvalley/32/206092_2.png) [@dvalley](https://forum.nachi.org/u/dvalley)\ **Post date:** [July 19, 2007, 5:45pm UTC](https://forum.nachi.org/t/furnace-ac-age-help/18551/3 "2007-07-19T17:45:54Z")
Thomas, When there are three or four letters at the start of the serial number, the third letter is the year. Y is 1991, A is 1992, B is 1993, C is 1994, D is 1995, and so on. Your third letter is **K** , so this York furnace was manufactured in 2001. The third letter in the A/C is **J** , so that was manufactured in 2000. ---
**Author:** ![dvalley](https://sea2.discourse-cdn.com/internachi/user_avatar/forum.nachi.org/dvalley/32/206092_2.png) [@dvalley](https://forum.nachi.org/u/dvalley)\ **Post date:** [July 19, 2007, 5:52pm UTC](https://forum.nachi.org/t/furnace-ac-age-help/18551/4 "2007-07-19T17:52:48Z")
Here’s the York codes for anything before 2005. When there are three or four letters at the start of the serial number, the third letter is the year. 1971 - A 1972 - B 1973 - C 1974 - D 1975 - E 1976 - F 1977 - G 1978 - H 1979 - J 1980 - K 1981 - L 1982 – M 1983 – N 1984 – P 1985 - R 1986 - S 1987 - T 1988 - V 1989 - W 1990 - X 1991 – Y 1992 – A 1993 - B 1994 - C 1995 – D 1996 - E 1997 - F 1998 - G 1999 - H 2000 - J 2001 - K 2002 - L 2003 - M 2004 - N 2005 - P ---
**Author:** ![swiegner](https://avatars.discourse-cdn.com/v4/letter/s/74df32/32.png) [@swiegner](https://forum.nachi.org/u/swiegner)\ **Post date:** [July 19, 2007, 9:41pm UTC](https://forum.nachi.org/t/furnace-ac-age-help/18551/5 "2007-07-19T21:41:51Z")
David Is Exactly Right