How to read York, Coleman and Luxaire serial numbers

This covers York, Coleman, Luxaire, Fraser-Johnston, Guardian, Johnson Controls. The serial number is on the rating plate. Many York labels also print the manufacture date.

Brand on the labelSerial number

Reading it yourself

Since October 2004: a plant letter, a digit, a month letter, then digits. The digit before the month letter and the digit after it make the year: 0 and 6 is 2006. The month letter skips I and J, so K is September and N is December.
Example: N0D6653823 was made in April 2006.
Before October 2004: four letters, then six digits. The second letter is the month, and the third letter is the year. Letters A to N each stand for two years, 21 years apart.
Example: EFBM210830 was made in June 1972 or June 1993.

This is the date the unit was made. It was usually installed soon after, but it can be later. If a serial doesn’t fit any of these patterns, look on the label for a printed manufacture date.

Sources

Checked in October 2026.

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