Fraser, Johnston and Luxaire were purchased by York in 1980.
York recently changed their serial nomenclature, so the old date sheets will not work in decoding anything manufactured after 2005.
YORK (Borg-Warner) (Unitary) Third letter in Serial Number
**A 1971 B 1972 C – D – E – F –(G 1977) H – J – K – L – M – N – (P 1984) **
R 1985 S 1986 T – V – W – X – (Y 1991)
A 1992 B 1993 C – D – E – F – G – H – J – K – L – M – N – (P 2005)
Since 2005 models have a letter-number-letter-number configuration. (SN: W0E5195159)
W=city of manufacture 0=third digit of year E=month 5=fourth digit of year
(Wichita) 200-? May 2005