Every effort is undertaken to offer you correct and concise information to assist you in determining the age or manufacture date of HVAC equipment. Anytime anyone is dealing with numbers and letters in determining data, mistakes and misinterpretation are bound to happen. For this reason if you find during your research that we may have erred please contact us. In addition perhaps you have come across a brand, model or serial number format that we have not addressed. Email us information or pictures of data/nomenclature plates of the unit and we will attempt to assist you in your determinations. Email
This page was last updated: 25 July 2009
Carrier (1980 - Present)
Date of Manufacture (1980 to Present): The manufacturing date code is the first, second, third and fourth digits of the Carrier serial number and represents the week and year of manufacture.
For example: 1790AD6607 indicate that this sample Carrier unit was manufactured in the 17th week of 1990.
Year of manufacture: 1790AD6607
Week of manufacture: 1790AD6607
Carrier (1970 thru 1979)
Date of Manufacture (1970 thru 1979): The manufacturing date code is the first and second digits of the Carrier serial number and represent the month and year of manufacture.
To determine year: 0 = 1970; 1 = 1971; 2 = 1972; 3 = 1973; 4 = 1974; 5 = 1975; 6 = 1976; 7 = 1977; 8 = 1978; 9 = 1979.
To determine month: A = Jan; B = Feb; C = Mar; D = Apr; E = May; F = Jun; G = Jul; H = Aug; I was not used; J = Sep; K = Oct; L = Nov; and M = Dec.
For example: A1 123456 indicate that this sample Carrier unit was manufactured in January 1971.
Year of manufacture: A1123456
Month of manufacture: A1123456
Carrier (Prior to 1970)
Date of Manufacture (Prior to 1970): The manufacturing date code is the first digit of the Carrier serial number and represents the year of manufacture.
For example: 1 123456 indicate that this sample Carrier unit may have been manufactured in 1931, 1941, 1951, 1961, etc. The date code was not an exact science and Carrier has been in business since 1902 making it difficult to establish the actual year of manufacture for any unit manufactured prior to 1970. Finding Carrier Units with this type of serial number still in use today would be extremely unlikely.