About A.O. Smith

The company was founded in 1874 in Milwaukee, Wisconsin, where today the Company is headquartered. A. O. Smith employs over 12,000 individuals at operations in the United States, Canada, Mexico, China, India, the United Kingdom and the Netherlands. We also have sales and distribution in more than 60 countries around the world.

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HVAC Age / Serial Decoder

Style 1

The first two numbers represent the year the heater was built. If your heater was built before 2008, the next two numbers represent the month. If your heater was built after 2008, the next two numbers represent the week.

Variant A
Example Serial Number
2
Year
2
Year
1
Week
3
Week
A
Ignored
1
 
2
 
3
 
4
 
5
 
6
 

This would read as 13th Week of 2022. Grey is ignored.


Variant B
Example Serial Number
S
Ignored
2
Year
2
Year
1
Week
3
Week
F
Ignored
1
 
2
 
3
 
4
 
5
 
6
 

This would read as 13th Week of 2022. Grey is ignored.


Variant C
Example Serial Number
2
Year
2
Year
1
Week
3
Week
1
 
2
 
8
 
9
 
1
 
4
 
1
 
7
 
7
 

This would read as 13th Week of 2022. Grey is ignored.

Style 2

Ignoring the first letter, the second letter represents the month, and the first two digits represent the year. The difference between Variant A and Variant B is the introduction of hyphens and overall length in Variant B.

Variant A
Example Serial Number
M
Ignored
B
Month
0
Year
3
Year
A
Ignored
1
 
2
 
3
 
4
 
5
 
6
 

This would read as February, 2003. Grey is ignored.


Variant B
Example Serial Number
M
Ignored
B
Month
0
Year
3
Year
-
 
1
 
2
 
3
 
4
 
5
 
6
 
7
 
-
 
S
Ignored
1
 
2
 

This would read as February, 2003. Grey is ignored.

Style 3

The first letter represents the month, and the first two digits represent the year. The difference between Variant A and Variant B is the introduction of hyphens and overall length in Variant B.

Variant A
Example Serial Number
A
Month
0
Year
3
Year
A
Ignored
1
 
2
 
3
 
4
 
5
 
6
 

This would read as January, 2003. Grey is ignored.

Contact Information for A.O. Smith
Phone Numbers

Tech Support and Warranties
(800) 527-1953
Replacement parts
(800) 821-2017

Email Addresses

Tech Support and Warranties
help@hotwater.com
Replacement Parts
contactus@hotwater.com

Addresses
A. O. Smith Corporate Headquarters
11270 West Park Place, Suite 170
P. O. Box 245008
Milwaukee, Wisconsin 53224
USA
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