How can I determine the age of an American Standard air conditioner or heat pump from the serial number?

Friday, November 29, 2019

Most American Standard units state the date of manufacture clearly on the data plate, usually at the upper right, but it is also encoded in the serial number. Either the first number or the first two numbers are the year of manufacture and here’s two examples.

    The only exception to this simple system is that some models manufactured during the 1980's thru the 90's, and specifically the Allegiance and Heritage lines, use the first letter of the serial number to encode the year of manufacture. 

W = 1983, X = 1984, Y = 1985, Z = 1986
B = 1987, C = 1988, D = 1989, E = 1990
F = 1991, G = 1992, H = 1993, J = 1994
K = 1995, L = 1996, M = 1997, N = 1998
P = 1999, R = 2000

So the “K” in the serial number of the data plate shown below indicates that the condenser was made in 1995. But, of course, it is also stated outright in the upper right of the label.

    To determine the size in tons of your American Standard unit, see our blog post How can I tell the size in tons of an American Standard air conditioner or heat pump from the model number? For the age of another brand or manufacturer, go to our blog post How do I determine the age of my air conditioner?

    To determine other key specs of your HVAC system, see one of these other blog posts: 

• How can I tell the size in tons of an American Standard air conditioner or heat pump from the model number?

How can I find out the SEER of my air conditioner?

How can I tell whether the condenser (outdoor unit) is an air conditioner or heat pump? 

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 

  To learn more about heating and air conditioning systems, see these other blog posts: 

My air conditioner won't turn on. What's wrong? 

How can I find out the size of my air conditioner? 

Where is the air filter for my central air conditioner and furnace? I can’t find it? 

Does an old air conditioner use more electricity as it ages? 

How did homes stay cool in Florida before air conditioning? 

What is wrong with an air conditioner when the air flow out of the vents is low?

Why has the thermostat screen gone blank? 

Why does it take so long to cool a house when an air conditioner has been off for a while? 

Why is my air conditioner not cooling enough? 

What are the most common problems with wall/window air conditioners?  

Will closing doors reduce my heating and cooling costs? 

   Visit our HEATING AND AIR CONDITIONING page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles. 

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