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How can I determine the age of an American Standard furnace from the serial number?
Sunday, January 12, 2020
There are two serial number formats:
1) 2002 to present - If the serial number is a 9-digit combination of letters and numbers that starts with a number, then the first number is the year. Beginning in 2010, the first two digits are the year. Examples of each type are shown below. Many units have the date of manufacture stated below the serial number.
2) 1983 to 2001 - If the serial number starts with a letter, then that is the encoded year. W = 83, X = 84, Y = 85, S = 86, B = 87, C = 88, D = 89, E = 90, F = 91, G = 92, H = 93, J = 94, K = 95, L = 96, M = 97, N = 98, P = 99, R = 00, Z = 01. So the serial number shown below indicates that the furnace was manufactured in 1992. Notice that the year that the letter indicates is corroborated by the 1990 year of the ANSI rating above it, which should be the same year or just a few years earlier.
Many, but not all, furnace data plates will also state the month and year of manufacture somewhere on the data plate, like the examples below.
To determine the age of a American Standard air conditioner or heat pump, go to our blog post How can I determine the age of an American Standard air conditioner or heat pump from the serial number?
To determine other key specs of your HVAC system, see one of these other blog posts:
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Field Guide for Home Inspectors, a quick reference for finding the age of 154 brands of HVAC systems, water heaters, and electrical panels, plus 210 code standards for site-built and manufactured homes, and the life expectancy rating of 195 home components. Available at amazon.com for $19.95.
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To learn more about heating and air conditioning systems, see these other blog posts:
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