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How do I determine the age of a Trane air conditioner or heat pump from serial number?

Friday, July 20, 2018

Unlike other manufacturers that encode the year of manufacture in their serial number, Trane prints it clearly, usually in the upper right of the data plate. Older Trane units have a metal plate that is stamped with their information and, if it is worn or dirty, you might have to wipe off the surface dirt and shine a flashlight across the surface of the plate obliquely to read the date etched into the metal.

    If the manufacture date is missing or not legible, there are three ways that the manufacture year may be encoded in the serial number. It may be the first two numbers:

Or only the first number of the serial number:

Or, if the serial number starts with a letter, here is how to translate it:

T = 1981, U = 1982, W = 1983, X = 1984
Y = 1985, S = 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 data plate below indicates the unit was manufactured in 1994, which is also verified at the upper right of the data plate.

    Also, see our blog post How can I tell the size in tons of a Trane air conditioner or heat pump from the model number?  

    To find out the age of another brand of air conditioner or heat pump, go to How do I determine the age of my air conditioner?,  which has a listing of all major manufacturers and links to instructions for decoding their serial numbers.

     And to figure out what all the other numbers listed on the condenser data plate mean, go to our blog post How do I understand the air conditioner or heat pump condenser label (data plate)?

    To find the age of other home components, go to How can I find out the age of a roof? and How do I determine the age of an electrical panel? and How do I determine the age of my water heater? For life expectancies, visit What is the average life expectancy of the components of a house? 

  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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