It’s not always easy to determine how old your water heater is just by looking at it. For many homeowner, it can be difficult to find out whether or not your water heater is still under warranty when it has issues.
Many of the AO Smith tanks have the date stamped on the label next to the model and serial number. For the tanks that do not display an actual date, it’s also part of the actual serial number.
The picture of the tank on the right is serial # GA97-3435912-240, which means this tank was build in 1997. It’s usually the third and forth digit of the serial number.
The Bradford White tanks can be a little tricky to find out how old they are. The manufacture date is also in the serial number of the water heater which is displayed on the white tag below the label. The first digit of the serial number is the year and the second is the month. The chart below shows the code for everything beyond 2004. If you notice tanks that start with X are from 2001 and P is from 1997.
State water heaters have the manufacture date listed in the serial number. The first two digits are the year and the second two are the week of the year. This tank was manufactured on the 24th week of 2009.
Older tanks prior to 2004 will use the second and third number listed. Serial # A02134562 means the tank was manufactured in 2002.
Whirlpool water heaters are also know as Envirotech and USCraftMaster water heater company. The manufacture date can be identified in the serial number. The first two digits are the month and the second two are the year. The image on the right shows a water heater manufactured in December of 2002.