Water Heater Age Lookup: Serial Number Guide by Brand
Find out when your water heater was made using its rating label, model number and serial number. This guide helps homeowners across the United States. Start with a printed manufacture date, then choose your brand below for decoding examples and official lookup resources.
Start with the water heater label
- Find the rating plate. Look for the label with the model and serial number, usually white or silver—not just the large yellow EnergyGuide label.
- Take a clear photo. Include the whole rating plate and every character in the model and serial number. Reduce glare and keep the camera square to the label.
- Check for a manufacture date. It may be labelled “MFG. DATE” or similar. If there is no clear date, open the brand guidance below.
- Keep installation records separately. The manufacture date tells you when the heater was made. An invoice or installation record tells you when it was installed.
A date code can be ambiguous, especially on older equipment. If the format does not match, confirm the full label with the manufacturer or ask WHE for help.
Water heater age lookup by brand
Select your brand to open its guidance. These examples describe specific manufacturer formats; they are not a universal serial-number decoder.
A.O. Smith water heater age
For the modern format illustrated in A.O. Smith’s US service guide, the first two digits identify the year and the next two identify the manufacturing week. Example: 1719… means week 19 of 2017. This is a week number, not a month.
Older formats can differ. Photograph the whole rating plate: on some formats, scanning the barcode alone can leave out the date code. If the label does not match this example, have A.O. Smith confirm it.
A.O. Smith serial-number guide (PDF, page 10) · Date-code and barcode format notice (PDF)
Rheem water heater age
Look for a printed manufacture date first. In Rheem’s published serial-number example, 1209D01234 means December 2009: 12 is the month and 09 is the year.
Use this example only when your label follows that format. If your serial number looks different, use the complete model and serial number to confirm the date with Rheem.
Rheem water-heater serial-number guide
Bradford White water heater age
Bradford White uses the first letter for the year and the second letter for the month. Its year codes repeat, so the first letter alone does not identify a unique year.
For example, a serial beginning AC indicates March, with A shown as 2004 or 2024 in the manufacturer’s current chart. Older units can belong to an earlier cycle. Confirm the correct year using the full label, model and available installation records.
Navien tankless water heater age
Use the complete model and serial number from the exterior label. Navien’s support guidance locates the serial on the right side of the unit, between two barcodes.
Navien’s public serial lookup checks registration; it is not an age calculator. Ask Navien to confirm the manufacture date when it is not printed clearly on your label.
Navien registration lookup · Navien warranty and serial-number help
Stiebel Eltron electric tankless water heater age
Find the model and full serial number on the rating plate. If a manufacture date is not clearly printed, ask Stiebel Eltron’s US support team to confirm it. Do not apply another brand’s date code to this label.
Rinnai gas tankless water heater age
Keep a clear photo of the full model and serial number. Use Rinnai’s support resources to confirm the manufacture date and the warranty information for your particular model.
American water heater age
American labels can vary by model and production period. Keep the entire serial number and model number when checking an older unit. The manufacturer’s warranty lookup is a useful starting point; ask support to confirm the manufacture date if the result is unclear.
American Water Heaters warranty lookup
State water heater age
Use the full model and serial number with State’s official lookup. Older formats may differ, so do not assume a letter or four-digit prefix has the same meaning on every State water heater. Ask the manufacturer to confirm an uncertain date.
Ruud water heater age
Ruud offers a dedicated water-heater age calculator. Enter the complete serial number from your label there, and keep the model number available if you need help confirming the result.
GE water heater age
GE-branded water heaters include different product generations, including traditional tanks and GeoSpring models. Use GE’s water-heater support guide to identify the correct resource for your model. A general GE appliance chart or a Rheem example should not be applied to every GE water heater.
Optional: use the WHE age helper in ChatGPT
Already use ChatGPT? Our existing Water Heater Age and Service Inquiry Expert offers another way to ask about your label. You can enter the brand, model and serial number or provide a clear label photo.
Open the WHE age helper in ChatGPT
This opens ChatGPT, where access and photo uploads depend on your account. AI can misread label characters or date codes. Check the characters it reads and confirm uncertain results with the official brand resources above.
What does the age tell you?
The manufacture date is a useful starting point when discussing maintenance, repairs or replacement. It does not, by itself, confirm warranty coverage, condition or how much life is left in the heater.
Tell us about leaks, changes in hot-water supply, recurring problems and any previous repairs, along with the age. We can help you decide what to check next.
Need help with your label in Palm Beach County?
Email a clear label photo to eric@waterheatingexperts.com or call 561-602-9062. Include the problem you are experiencing and your city so we can help with the next step.
Water Heating Experts is family owned and master plumber owned, serving Palm Beach Gardens, Jupiter, Tequesta, Juno Beach, Wellington, West Palm Beach and Palm Beach County.
You can also explore repair and maintenance services or learn about water heater installation.
Water heater age questions
Is the manufacture date the same as the installation date?
No. A heater may have been manufactured before it was installed. Keep the purchase and installation records, and check the warranty terms for your model rather than assuming coverage from its age.
Can I find the age using only the model number?
The model number identifies the product, but it usually does not identify when your individual heater was made. Keep the serial number and any printed manufacture date with the model information.
What if the label is faded or the serial number does not match?
Do not guess missing characters. Try a clear photo with better lighting and check your installation paperwork. Send the information you can read to WHE or the manufacturer for help.
Does an older water heater automatically need replacement?
Age alone is not a diagnosis. Condition, performance, repair history and the problem you are experiencing all matter when discussing repair or replacement.