How To Determine The Age Of Your Water Heater

Looking to figure out how old your water heater is?

You might have just bought a home. Or maybe your water heater was there when you moved in years ago.

Either way, it’s important to know at least the year that your home’s water heater was made, so you’ll know when to start planning for a replacement.

One of the most important appliances you can buy, a water heater can last anywhere between 10 to 20 years. Your water quality, how often you drain and maintain it, and Calgary’s cold climate can all affect its lifespan.

In this guide, our Calgary hot water installers will go over how to determine the age of most types of water heaters found in Alberta.

Each water heater manufacturer uses its own serial number coding system that contains the date the water heater was made.

Your first step is to find your water heater’s manufacturer label. This can be pretty much anywhere on a hot water tank, and usually on the side of a tankless water heater.

Once you’ve found it, you should have your serial code, which you’ll need to decode to know the creation date.

Read our expert Airdrie plumber’s breakdown of how to read serial numbers for some of the most common water heater brands.

John Wood Water Heaters

For John Wood water heaters, the first two digits represent the year, and the next two indicate the week of production.

For example, a serial number starting with “2308” means the unit was manufactured in the 8th week of 2023.

Bradford White Water Heaters

Bradford White water heaters use a letter-and-number combination that tells you the year and month of manufacture.

The first letter is the year (starting with “A” for 2004, “B” for 2005, and so on), and the number that follows is the month (“1” for January, “2” for February).

For example, “A2” tells you the heater was made in February, 2004.

The letters repeat every 20 years. So a heater from 2003 would start with a Z.

Navien Water Heaters

Navien water heaters use four serial number formats, with the manufacture date embedded in each.

Here’s how to decipher them:

Style 1, no dashes, four digits after letter: In some Navien serial numbers without dashes, there will be five or six numbers in a row immediately after the first letter. The first two numbers are the year, the next one or two numbers represent the month, and the last two numbers represent the day.
For example, in 9545J1152752044, the date of manufacture is May 27, 2011.

Style 2, no dashes, two digits after letter: In other Navien serial numbers without dashes, there will be two numbers in a row immediately after the first letter, followed by another letter. The two numbers represent the year.
For example, in 7414C14X1771143, the year of manufacture is 2014.

Style 3, two dashes: In Navien serial numbers with two dashes, the four numbers after the first dash are the year, the next one or two numbers are the month, and the last one or two numbers are the day.
For example, in 9262-20081208-1027, the date of manufacture is December 8, 2008.

Style 4, three dashes: In Navien serial numbers with three dashes, it’s the same as style 3, only there’s a dash separating the year and the month.
For example, in 9010-2008–114-1014, the date of manufacture is January 14, 2008.

Note: the day of manufacture will always have two digits, but the month may have only one. So “114” always reads as January 14, and not November 4.

Rinnai Water Heaters

Rinnai water heaters also include the manufacturing date within the serial number. The first two numbers are the year, and the second two numbers are the month.

For example, in 18031234567, the month of manufacture is March, 2018.

Rheem Water Heaters

In Rheem’s serial numbers, in the first four numbers, the first two digits are the month, and the second two digits represent the year.

For example, in 1114D1234, the month of manufacture is November, 2014.

A.O. Smith Water Heaters

In A.O. Smith water heater serial numbers, ignore any letter at the beginning. Then, the first two numbers you come across will 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.

For example, in U0106413635, the heater was manufactured in June 2001.

Can’t Find the Age of Your Water Heater?

If figuring out the age of your water heater from the serial number feels overwhelming or you just can’t find the serial number, don’t worry—we’re here to help.

Some older models can have faded or damaged labels, while others can just seem confusing.

You can always call us and have a skilled water heater technician inspect your home’s water heater.

A skilled technician can:

Accurately identify the manufacture date
Assess the overall condition of your water heater
Provide recommendations for maintenance or replacement
Help you understand the remaining expected lifespan of your unit

Whether you have a tankless water heater or a hot water tank, if your water heater is starting to have problems like making strange noises, leaking at the base, pilot light issues, or your hot water is suddenly too hot, our techs can help.

Thinking about a replacement? See: Pros and Cons of a Tankless Water Heater in Alberta.

Contact Us for a Professional Inspection

If you’d like to have a professional inspection done on your home’s water heater, we’re at your service!

With nearly 40 years of hot water tank maintenance and inspection experience in Calgary, respectful and certified technicians, and a 100% satisfaction guarantee, we’re here to put your mind at ease. We service, repair, and install both hot water tanks and tankless water heaters.

Request an on-site quote today or give us a call to talk to one of our specialists!