If the first digit of the serial number is a letter, then use the letter code system below to determine the year of manufacture.

H = 1998    A = 1999    B = 2000    C = 2001
D = 2002    E = 2003    F = 2004    G = 2005
J =  2006    K = 2007    L = 2008    M = 2009
N = 2010    P = 2011    Q = 2012    R = 2013
S = 2014    T = 2015    U = 2016    V = 2017
W = 2018    X = 2019    Y = 2020    Z = 2021

    If the first two digits are numbers, then they are the year of manufacture. This means the unit was built early 1998 or before. So, for example, 94D142831 was produced in 1994, and P122247312 was manufactured in 2011.

    To determine the size of your Climatemaster unit, see our blog post What size in tons is my Climatemaster heat pump? 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: 

• What is the best location for a heat pump condenser (outside unit)?

• What is the best location for a heat pump air handler (indoor unit)? 

• 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? 

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

  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.