How do I tell the age of a Fedders furnace or air conditioner from the serial number?

Sunday, August 19, 2018

The second letter of the serial number indicates the year of manufacture (from 1966 to 1977): 

A = 1966    B = 1967   C = 1968    

D = 1969   E = 1970   F = 1971

G = 1972   H = 1973   I = (not used)

J = 1974   K = 1975   L = 1976   M = 1977

    An ancient Fedders unit we recently inspected had the serial number AH11877, indicating that it was manufactured in 1973. The home was built in 1973, which provided a secondary verification of the manufacture date indicated by the serial number.

    Also, see our blog posts Why is my air conditioner not cooling enough? and How can I find out the SEER of my air conditioner?

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  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? 

How can I find out the age of my air conditioner or furnace?

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

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? 

When should I switch my thermostat to “EMERGENCY HEAT” for my heat pump air conditioner?

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

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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