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Determining Whirlpool Water Heater Age (3 Methods)

Fact checked by Stephen Conklin

whirlpool water heater age

We all want to learn about our Whirlpool water heater age or any other similar appliance. That way, we’ll know when to expect to see wear and tear-related issues and anticipate a replacement.

The most definitive way of determining the age of Whirlpool water heater units is by checking their serial numbers. Otherwise, you can always search online, read the User Guide, or contact Whirlpool representatives.

Worry no more because we’ll describe how to tell your Whirlpool water heater’s age.

Table of Contents

Determining the Age of a Whirlpool Water Heater

“How old is my Whirlpool water heater?” Many beginner water heater owners ask this question. Although the answer seems complicated, the solution is straightforward.

The most conclusive method for determining the appliance’s age is checking its serial number. Of course, other tricks are available when the serial number lookup doesn’t yield the expected results. Let’s discuss these methods one by one.

1. Using the Serial Number On The Manufacturer’s Label


Defining a Whirlpool water heater’s age by serial number is fast and easy, as these digits describe the year and week of manufacture. You can find this information on the manufacturer’s label stuck to the unit body.

When buying water heaters from this brand, chances are that you’ll see two types of serial numbers:

  • An 11-character alphanumeric string with the following format: YYWW*******. There should be a single letter that separates the “YYWW” section from the last six digits.
  • A 10-digit number series (without a letter on the element or position). For example, you might see a “0128104380.”

In any case, the reading method for these date codes is the same. You only need the first four numbers in either Serial information to determine the age of your Whirlpool water heater.

  • The first two digits (YY) on the alphanumeric string or number series represent the appliance’s year of manufacture. Hence, “o2” denotes an old 2002 model, while “22” indicates the latest model (2022).
  • The second two digits (WW) after the manufacturing year identifier relate to the nth week of manufacture. For example, the Serial Number “0128104380” represents a manufacturing date in the 28th week of 2001.


So, if the first four digits read 1235, you can infer that its manufacture date is in the 35th week of 2012 (between Aug. 27 and Sept. 2, 2012).

You don’t need a serial number decoder for this. As for the last six digits in the alphanumeric or number series, they identify the Whirlpool water heater’s Sequence Number.

On the manufacturer’s label, you’ll also find the heater’s model number, product number, and technical specifications. You can look up the model number online to learn when the model was introduced.

2. Other Ways of Determining Whirlpool Water Heater Age


Suppose you want to ensure your Whirlpool water heater’s age but can’t read the manufacturer’s printed information. You can try reading the Owner’s Manual or User Guide. Most manufacturers also place critical data in these documents. Otherwise, you can try the following tricks.

  • Code search web pages – The internet is a treasure trove of beneficial resources. You can try searching for your Whirlpool’s manufacturing date information online. Unfortunately, you will need the Serial number in most cases.

Alternatively, you can post a query on online community forums, preferably in Whirlpool water heater owner groups. They will be more than happy to guide you in your search.

  • Contact manufacturer – There’s nothing wrong with contacting Whirlpool via their customer service and asking about your water heater’s age. Sadly, they might require the Serial number, which is a fundamental need for the company’s warranty check

Your dealer, sales representative, or distributor can also help you. They might need some information about your Whirlpool water heater, though.

If you can’t get your hands on the model or serial number, try taking photos of your water heater from various angles. Provide whoever you contact with a detailed description of its features. This way, you can have a rough estimate of when the model was introduced.

  • Have a look at the user manual—If you still have the user manual that comes with the Whirlpool water heater, you’re in luck. Try looking through the manual—the date of production should be in there.Even if you can’t find the exact date of production in the manual, you should still be able to learn the heater’s serial number. And as explained, the serial number will indicate when the appliance was produced.

3. Whirlpool Water Heater Age Chart

As mentioned, you will notice two Serial number formats for Whirlpool water heaters. The good news is you only need to concern yourself with the first four digits because they represent the appliance’s year and week of manufacture.

Format Example Manufacturing Date
Style 1 YYWW#****** 1543T909754 43rd week of 2015 with sequence number 909754
Style 2 YYWW****** 0118762345 18th week of 2001 with sequence number 762345

Why Knowing the Age of a Water Heater is Important

Most storage tank-type water heaters last eight to a dozen years, although tankless units can last much longer—up to 20 years or more.

On the other hand, gas-powered water heaters have a shorter lifespan than electric versions, lasting only about six to eight years.

So why would you care about your water heater’s age?

Knowing your water heater’s age lets you prepare for a replacement. For example, if your heating appliance is already ten years old and showing signs of deterioration and poor functioning, it’s more practical to buy a replacement unit than repair the water heater.

In addition, learning a water heater’s age helps you determine whether it’s still fit for warranty verification. For instance, Whirlpool only covers its water heaters for a year, while Rheem offers a six-year limited guarantee for its water heater tank and parts. You can also extend it to ten years.

Lifespan of a Whirlpool Water Heater

So, how long can you expect your Whirlpool to continue delivering hot water?


1. Life expectancy

The average Whirlpool water heater can last 10 to 12 years, provided that you flush the tanks and perform maintenance checks at least once per year.

2. Signs that indicate a Whirlpool water heater replacement

Many signs can warn you of an impending Whirlpool water heater replacement. Age is one (which we already discussed). The inability to deliver hot water, inadequate hot water production, or water not hot enough can also be a warning that the appliance is near-failing.

Other signs that tell you it’s time for a new water heater include unusual sounds from the appliance, persistently low water pressure, water discoloration, and leaks.

3. Maintain and extend the life of a water heater

Can a water heater last 35 years? It’s very rare that a water heater can reach such an age. However, there are several things you can do to prolong its lifespan:

  1. Observe periodic maintenance and professional servicing
  2. Prevent limescale buildup with a water softener
  3. Install a thermal expansion tank
  4. Frequent assessment of water heater components, including gas lines, anode rods, and temperature-pressure (T&P) relief valves
  5. Drain and flush the water heater at least once annually
  6. Insulate the water heater and plumbing system

Whirlpool Vs. Other Water Heater Brands


Telling a Whirlpool water heater’s age is as straightforward as identifying the first four digits in its Serial Number, representing the manufacturing year and week. But how about other water heater brands? Let’s find out.

1. Rheem

Rheem uses a nine-character alphanumeric string to define its water heater’s manufacturing date. It differs from Whirlpool by observing an “MMYY*****” (month-year) format.

2. O. Smith

A.O. Smith water heaters produced before 2008 have a Serial Number with an “*MYY******” format, while post-2008 versions feature a “YYWW*******” style.

To tell whether yours is a pre- or post-2008 model, count the number of digits in the Serial Number. Those with 10 digits were produced before 2008, whereas those with 11 were manufactured after.

3. Bradford White

Bradford White water heaters use a nine-character alphanumeric string, with the first two characters as letters representing the year and month of manufacture.

The year model starts with the letter “A” for 1984 and ends with “Z” for 2003. For 2004, the year model again cycles to “A.” Months correspond with the alphabet’s first 12 letters. So, KH6511396 suggests a manufacturing date of August 2013.


Determining the Whirlpool water heater age is as easy as locating the appliance’s Serial Number and interpreting its first four digits. The first two numbers reflect the manufacturing year, while the second two-number set identifies the water heater’s manufacturing week.

The question is where you should look for Whirlpool’s Serial Number. Most water heaters have a manufacturer’s label on the appliance’s side or wall. Alternatively, the information might be in the User Guide or product documentation.

Knowing the Whirlpool water heater’s age lets you determine the need for a replacement or ascertain its warranty coverage validity.

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