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How old is my water heater?

Sunday, December 5, 2021

Use serial number to find age of your water heater

The year of manufacture of your water heater is encoded in the serial number on the data sticker. It is usually the first two numbers or second two numbers in the series, but varies by company and some use a single letter to indicate the year. Click on the brand of your water heater below to go to a page with instructions on how to interpret that specific manufacturer's serial number, along with examples. If you can’t find you water heater on the list or the serial number is not legible, keep reading further down for a solution.

A.O. Smith   American  American ProLine  
Ariston  Bosch Bradford White 
Craftmaster  Eccotemp  EcoSmart  
Eemax  Envi-Ro-Temp   GE  GSW  
Intertherm Jackson  Jacuzzi  
John Wood  Kenmore  Insinkerator  
Marey    Maytag   Mor-Flo   Navien  
Noritz  Paloma  Premier Plus   
Reliance   Rheem Rheem tankless    
Richmond    Rinnai   Ruud  Seisco   
SioGreen  State Industries   
Stiebel Eltron  Takagi  Tempra  
Therm-a-flow Tiny Titan  Titan  
Thermalux   Triangle Tube  
US Craftmaster  Westinghouse  

Can’t find your water heater in the list?

There are less than a dozen major manufacturers of water heaters, but many sell under multiple brand names. More than a hundred names have been used and then abandoned over the years, and many of them are the same as the major retailers that sell them, such as Lowes or Ace. We can’t list them all here. But, if you look closely for the fine print on the data sticker, you are likely to find the actual manufacturer’s name to use to decode the serial number. Here’s an example below.

Can’t find the serial number?

Still stuck? Go to our blog post How can I determine the age of a water heater if the serial number is missing or decoding it is impossible?  

Here’s links to a collection of more blog posts about WATER HEATERS:

What can I do to make my water heater last longer?

Are water heaters required to be raised off the floor? 

What's that powdery crust on the pipe connections at the water heater? 

What are the most common installation mistakes with water heater replacement?

What is backdrafting at a gas water heater? 

Where are gas water heaters not allowed to be installed?  

Is the minimum size water heater inlet pipe 1/2" or 3/4" according to the building code?

Can you use a light switch for a water heater disconnect? 

How can I tell if a water heater is HUD-approved for mobile/manufactured homes?

Can you wire a 240-volt water heater with 120 volts? 

Is it alright to have a shut-off valve on both the hot and cold water pipes at a water heater?  

Why is the water heater older than the house? 

Does a water heater need a shut-off valve? 

Why should a tankless water heater have an isolator/service valve kit installed?

When was a gas water heater first required to be elevated 18 inches above a garage floor?  

Can the temperature and pressure relief (TPR) valve discharge pipe for a mobile/manufactured home water heater terminate under the home? 

What is the purpose of a thermostatic mixing valve above a water heater? 

Does a tankless gas water heater still work with no electricity during a power outage?  

Why do water heaters have a sacrificial anode? 

What is the difference between a manufactured/mobile home water heater and a regular water heater? 

Does a tankless water heater require a pressure relief valve?

When is a water heater drain pan required?

   Visit our WATER HEATERS 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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