York serial age
Manufacture date from the rating-plate serial. Same family as Coleman, Luxaire, Fraser-Johnston. A printed MFR date on the plate still wins.
York
Type the serial off the rating plate. Spaces and hyphens are ignored. Manufacture date is not the install date.
Diagnose this call
Age is open. The walkthrough is the seat.
Where the plate is
Ten-character serial on the rating plate. Outdoor units: side panel.
Styles
2004–present
W0K5896070
Year is the 2nd and 4th characters concatenated (0 and 5 → 05 → 2005). Third character is the month letter. W0K5… = November 2005.
1971–2004
WAKM011379
Second letter is month, third letter is year. Letter-year values are plant-specific — open the Building Intelligence Center York page rather than guessing.
Same date-code family: Coleman.
Cross-checked against York HVAC age. FieldBench does not host or republish that page. Letter charts we could not verify are linked out instead of invented.