Here is what I have. Doesn’t look like it helps you much. Try calling the number for information.
Carrier, Bryant, Payne, Day & Night: Recently (since 1990?) the first four numbers in the serial number represent the week and year. Previously, it was a complex series of letters and single digits. See below or call 905-672-0860 if you get stuck.
ANNNNNN This serial number was used from 1969 to 1990. The first alpha character is for the month of production. A-M = Jan-Dec 1969-1979
N-Z = Jan-Dec 1980-1990 ‘I’ and ‘O’ are not used The second digit, a numeric character is the production year The balance of the numeric characters are the production sequence e.g., A912345…this serial number would be a unit produced in Jan 1969