State Water Heaters ships products to over 60 countries, which is impressive for a brand with humble roots. However, figuring out exactly when your specific unit was built isn’t always straightforward.
Whether you are checking warranty status or hunting for spare parts, knowing the manufacture date is essential. We’ll help you decode the serial number so you can pin down your State water heater’s exact age in seconds.
Key Takeaways
- Check the rating plate: You can find the manufacturing date hidden within the serial number on the unit’s data sticker.
- Modern style (Post-2008): The first four digits usually represent the year and week of manufacture (YYWW).
- Legacy style (Pre-2008): Older units often use a letter to represent the month, followed by numbers for the year.
- Warranty check: Verifying the age helps you determine if your unit is still under warranty or due for replacement.
How Old Is My State Water Heater?
To the untrained eye, the string of numbers and letters on your water heater’s rating plate looks like a random password. Fortunately, it’s actually a logical code. The age of your gas or electric State water heater is hidden directly inside the serial number.
Since A.O. Smith acquired State Industries, the coding formats have changed slightly over the years. Generally, you will encounter one of two main styles: the modern “Year/Week” format or the legacy “Letter/Year” format.
Here is how to crack the code.
Style 1: The Modern Standard (First Four Digits)
If your water heater was made recently (specifically after the 2008 acquisition by A.O. Smith), this is the most likely format. It is also the easiest to read.
The first four numbers of the serial code represent the year and the week of manufacture.
- Example Serial: 1810A002243
- The Code: 1810
- The Year: 2018 (First two digits)
- The Week: 10th week (Third and fourth digits)
In this example, the unit was built in early March of 2018.
Style 2: The Letter Method (Legacy Models)
Older State units, and some specific “State Select” models, use a letter to start the serial number. This letter corresponds to the month of production, while the following numbers indicate the year.
You will need this chart to translate the letter into a month:
| Letter Code | Month | Letter Code | Month |
| A | January | G | July |
| B | February | H | August |
| C | March | J | September |
| D | April | K | October |
| E | May | L | November |
| F | June | M | December |
Note: The letter “I” is skipped to avoid confusion with the number “1”.
Let’s look at a few examples of how this plays out in the real world.
Example A: H04123456
- H: August
- 04: 2004
- Date: August 2004
Example B: M99123456
- M: December
- 99: 1999
- Date: December 1999
Pro Tip
If your serial number starts with two letters (like AF04), look at the second letter for the month and the following two numbers for the year. The first letter is just a factory code. For example, AF04 means June (F) of 2004.
When Should I Replace My State Water Heater?
State Industries is known for durability, often testing their units in extreme conditions to ensure they last longer than generic brands. However, even the best tanks have an expiration date. You can typically expect a lifespan of 10 to 15 years.
Watch out for these warning signs:
- Strange Noises: Rumbling, banging, or popping sounds usually indicate sediment buildup hardening at the bottom of the tank.
- Slow Recovery: If the unit takes longer to heat the water than it used to, the heating elements or burner may be failing.
- Leaks: Any moisture around the base of the tank is an immediate red flag.
- Rising Bills: If your energy costs spike without a change in usage, your heater is losing efficiency.
Water Heater Maintenance Tips
You don’t have to wait for a breakdown to give your water heater some attention. A little preventative maintenance goes a long way toward extending the life of your unit.
Flush the Tank Annually
Sediment is the enemy of water heaters. Minerals settle at the bottom of the tank, creating a layer of “scale” that insulates the water from the heat source. Flushing the tank once a year washes these deposits away and keeps your system efficient.
Check the Anode Rod
Think of the anode rod as a “sacrificial lamb.” It attracts corrosive elements in the water so they attack the rod instead of the tank lining. When the rod is depleted, the tank starts to rust. Check it every 2-3 years and replace it if necessary.
Lower the Temperature
Turning your thermostat down to 120°F (49°C) relieves strain on the elements and tank walls. It also reduces the risk of scalding. You likely won’t notice the change in water temperature at the tap, but you will notice the savings on your monthly bill.
Add Insulation
While modern State tanks have good internal insulation, adding an external insulated jacket can further boost thermal efficiency. This is especially helpful if your water heater is located in a cold garage or basement. It keeps the water hot for longer, meaning the unit fires up less frequently.
Repair Components Early
Don’t ignore small issues. If a valve sticks or a pilot light flickers, fix it immediately. You can buy most spares like gas control valves or thermocouples online. Catching these problems early prevents them from causing catastrophic tank failure later.
FAQs
Where is the serial number located on a State water heater?
You can find the serial number on the rating plate, which is a sticker usually located on the side of the tank near the bottom. This sticker also contains model information, wattage, and capacity details.
How long is the warranty on a State water heater?
Most residential State water heaters come with a 6-year limited tank and parts warranty. Some premium models offer 10-year coverage, while commercial units may vary. Always verify your specific warranty status using the serial number on the manufacturer’s website.
Who manufactures State water heaters?
State Water Heaters is owned by A.O. Smith Corporation. A.O. Smith acquired State Industries in 2001, which is why modern State serial numbers follow the standard A.O. Smith coding format.
The State of Your Water Heater
Knowing the age of your State water heater gives you power. It tells you if you are covered by a warranty or if you should start budgeting for a replacement.
By checking the first four digits or the letter code on your data plate, you can solve the mystery in seconds. Keep that tank flushed, check your anode rod, and enjoy your hot showers.
