Your Whirlpool water heater’s age can be determined by the serial number located on the unit, where the first two digits typically indicate the year of manufacture.
Knowing your water heater’s age helps predict its remaining lifespan and plan for replacements. Whirlpool water heaters use serial numbers to indicate manufacture dates, but decoding them requires specific knowledge.
Locating Your Whirlpool Water Heater’s Serial Number
The serial number appears on the manufacturer’s label, typically found on the upper portion of the tank. You’ll usually see it near the:
- Energy Guide label
- Technical specifications
- Installation instructions
Common Serial Number Formats
Whirlpool uses two primary serial number formats:
| Format Type | Example | How to Decode |
|---|---|---|
| Letter Prefix | A1234X567 | First letter indicates year (A=1987, B=1988…) |
| Numeric Prefix | 1234A5678 | First four digits indicate manufacture date (MMYY) |
Decoding Letter-Prefix Serial Numbers
For older Whirlpool water heaters (pre-2000s), the first letter indicates the manufacture year:
- A = 1987
- B = 1988
- C = 1989
- …
- Z = 2012
After 2012, Whirlpool typically switched to numeric date codes.
Understanding Numeric Date Codes
Modern Whirlpool water heaters use a 4-digit date code at the serial number’s beginning:
- First two digits: Month (01-12)
- Last two digits: Year (00-99)
Example: 1209X12345 = December 2009 manufacture date.
Special Cases and Exceptions
Some units may show:
- Additional letters after the date code (usually factory codes)
- Dashes or spaces separating components
- Different formats for commercial models
Whirlpool Water Heater Lifespan
Average lifespan ranges from 8-12 years depending on:
- Water quality (hard water reduces lifespan)
- Maintenance frequency
- Installation quality
- Usage patterns
Consider descaling your water heater if you have hard water to extend its life.
Common Whirlpool Water Heater Issues
Older Whirlpool models (2000-2005) had known thermocouple problems causing pilot light failures. Whirlpool offers free conversion kits to fix this issue.
For modern units, watch for:
- Sediment buildup (causes rumbling noises)
- Corroded anode rods
- Leaking pressure relief valves
Learn about anode rod replacement to prevent tank corrosion.
When to Replace Your Water Heater
Consider replacement if your Whirlpool water heater:
- Is over 10 years old
- Requires frequent repairs
- Shows rust-colored water
- Leaks from the tank
- Fails to maintain temperature
For replacement options, compare heat pump vs tankless water heaters.
Manufacturer Support
Whirlpool provides:
- Phone support: 877-817-6750
- Online manuals and documentation
- Warranty service for qualifying units
For more information about water heater maintenance, visit the U.S. Department of Energy’s water heating guide or the official Whirlpool water heaters website.
