Dating Residential Furnaces & Central A/C
The following are brands of furnace and central air conditioners commonly found in southeast Michigan. This list is not an all encompassing list, however, a contentious effort was made to provide the correct information to assist in determining the age of the HVAC (Heating, Ventilation, and Air Conditioning) equipment despite the numerous manufactures and the variations of dating codes.
First, when dating an HVAC unit, first look at the data tag, the manufacturing date may be displayed on the data sticker.
Second, look for the serial number. Sometimes the date is hidden within the serial number. For example, C12 could indicate that the water heater was constructed in March of 2012. Also look at the serial number. If there are 4 numerals at the start of the serial number, the first two numbers could represent the year, the next two numerals could represent the month or the week of manufacture, or vice versa. Compare this information to the “ANSI” (American National Standards Institute) or “CSA” (Canadian Standards Association) code dates described in the following paragraph.
Third, if the date of manufacture is not immediately evident a little sleuthing around the label may reveal the date of manufacture. Look at the lower portions of the data sticker for the letters “ANSI” or “CSA”. The four digits after the referenced standard authority usually represent the code or standards to which the furnace or air conditioner was constructed. For example, the if the “ANSI” or “CSA” year is 2006, the unit was likely constructed during a three, possibly six year window from 2007 through 2012.
Finally, if all else fails look for the brand and the serial number in the following paragraphs:
Amana (A member of the Goodman and Janitrol family of furnaces.)
For units manufactured since the early 1990’s, the first two placeholders in the serial number indicate the year (“Y”), and the next two numbers indicate the week (“W”) of manufacture (YYWW).
American Standard (Trane and Unitary)
Newer American Standard products have the month and year of manufacture on the date sticker. If the date is not readable or present on the data sticker, American Standard uses several dating codes in their serial numbers. The first code format would is the production year is the first numeral in the serial number followed by the week (YWW). A second code format is the first placeholder in the serial number is a letter representing the month followed by two digits for the year (MYY). An older code format is the first two digits of the serial number represent the year, and the next two digits represent the month (YYMM)
Arcoaire
See “International Comfort Products”
Armstrong
Armstrong uses three methods of imbedding the date codes in the serial numbers. With the first method, the first two numerals of the serial number represent the year, and the next two numerals represent the week (YYWW). The second method uses the first two digits of the serial number represent the week, and the third and forth numbers represent the year of manufacture (WWYY). The third method uses the third and fourth placeholders of the serial number are numerals that represent the year of manufacture. The letter after the year is a letter that represents the month (**YYM).
Bryant (Carrier, Payne)
For Bryant, Payne, and Carrier HVAC products manufactured form 1985 to the present, the date code is embedded in the first four placeholders of the serial number. The first two numerals in the serial number is the week of manufacturer (01 to 52 weeks in the year), and the third and fourth digits are the year. For example, the date code in this serial number “2901A18288” is the 29th. week of 2001.
Carrier (See “Bryant”)
Coleman (see York)
Comfortmaker
See “International Comfort Products”
Ducane (Also see Lennox)
Ducane uses several serial number date codes. For example, the third and forth placeholders in the serial number is the production year followed by a letter for the month (**YYM). Another variation of their code is the second and third placeholders are the year and the fourth and fifth placeholders are the week (*YYWW).
Evcon (see York)
Fraser-Johnson (see York)
General Electric
In general, all of the General Electric furnaces, central air conditioners, and central heat pumps were last manufactured in the mid 1980’s. These units are beyond the expected service life. Note that “Trane” acquired the HVAC product line from General Electric and that “American Standard” acquired “Trane”.
Gibson (see Nordine)
Goodman (Goodman brands include Amana, Janitrol)
For units manufactured since the early 1990’s, the first two placeholders in the serial number indicate the year, and the next two numbers indicate the week of manufacture (YYMM).
Heil
See “International Comfort Products”
International Comfort Products (This product family includes Arcoaire, Comfortmaker, Heil, Kenmore, Tempstar)
The first place holder in the serial number is a letter for the month followed by two numerals representing the year (MYY).
Another method of dating some International Comfort Products equipment is the serial number starts with an “L” followed by two numerals the represent the year (LYY).
Janitrol (A member of the Goodman family of furnaces.)
For units manufactured since the early 1990’s, the first two placeholders in the serial number indicate the year, and the next two numbers indicate the week of manufacture (YYMM).
Kenmore
See “International Comfort Products”
Lennox
After 1974, the numerals in the third and forth placeholder of the serial number (**YYM****)indicate the year, and the fifth placeholder is a letter the represents the month. The month codes are A=January, B=February, C=March, D=April, E=May, F=June, G=July, H=August, J=September, K=October, L=November, M=December. (“I” is omitted as it looks like the numeral “1”).
Luxaire (see York)
Magic Chef (1980 through 1998)
The date code for Magic Chef is in the third and second from last place holders in the serial number. The third from last letter is the month, and the second from last letter is the year. (****MY*)
The month codes are A=January, B=February, C=March, D=April, E=May, F=June, G=July, H=August, J=September, K=October, L=November, M=December. (“I” is omitted as it looks like the numeral “1”).
Nordine (Gibson)
Nordine uses several codes
- The first method is the fourth and fifth placeholders in the serial number is the year, and the sixth and seventh place holders are the month (***YYMM).
- The second method uses the numerals in the third and forth placeholders for the year (**YY).
Payne
See “Bryant”
Rheem and Ruud
In the middle of the serial number will the letter “F” or “M”, the following four numbers are the week and the year. (“F”WWYY) or (“M”WWYY)
Trane
See “American Standard”
York (In Michigan, the common members York family include: Coleman, Evcon, Frasier-Johnson, and Luxaire.)
The York family of HVAC equipment uses several date codes, some inherited by acquisitions of other brands. The following three formats can help date the majority of the HVAC units in the family:
The simplest format is first two numbers in the serial number are year, the next two numbers are the month (YYMM).
For 2005 and after, a ten-place serial number is used. The first place holder is a letter, the second place holder is a digit which represents the first number of the year manufactured, the third place holder is a letter followed by the fourth place holder being a digit that represents the second number of the year manufactured. For example, the serial number of “W1E3062387”, the date of manufacture was in “2013”.
For 2004 and previous years, the third placeholder in the serial number is a letter. This letter represents the year. Y=1990, Z=1991, A=1992, B=1993, C=1994, D=1995, E=1996, F=1997, G=1998, H=1999, J=2000, K=2001, L=2002, M=2003, N=2004.