TankBirthday

Envirotemp Water Heater Age by Serial Number — Free Lookup

A.O. Smith

Also works for A.O. Smith-built labels: State, Reliance, American, Whirlpool, U.S. Craftmaster, Kenmore, GSW and John Wood.

How Old Is Your Envirotemp Water Heater?

Envirotemp is a private-label trade name produced on A.O. Smith (American Water Heater) production lines, so its serial numbers carry the same date code as State, Reliance, and American units: year, then week, in the first four digits. Enter your serial in the free decoder above for an instant answer, or follow the guide below to read it yourself.

Where to Find the Serial Number

Check the rating plate on the side of the tank — a silver or white sticker, usually in the upper half, that lists the model and serial numbers together. The date code lives in the serial, not the model number. If the sticker is worn, wipe it down and photograph it with the contrast bumped — you only need the first four digits.

How the Envirotemp Serial Format Works

The date code is year, then week, in the first four digits:

Worked example — 1007C001224:

  • 10 = 2010 (year)
  • 07 = week 7 (mid-February)
  • C and the remaining digits = factory and production sequence
  • Result: manufactured in week 7 of 2010

Letter prefixes. Some serials start with letters or contain a letter inside the date block — those are factory or product-line codes. Skip them and read the first four digits you find. For example, AB0709D009811 decodes to week 9 of 2007.

The two-digit year can point at two decades — 10 means 2010 on most units but could be 2000 on an older one. Compare the unit's condition and model line; our decoder lists every plausible year rather than guessing.

Why Your Envirotemp Water Heater's Age Matters

  • Lifespan. Tank water heaters average 8–12 years of service. Past that, internal corrosion makes tank failure — and a flooded floor — far more likely.
  • Warranty. Envirotemp tanks carried standard 6- and 12-year warranty tiers counted from the manufacture date. The serial tells you whether a repair might still be covered.
  • Home inspection. An Envirotemp unit past 10 years is a line item on any home inspection report; decoding the serial before you list or buy lets you negotiate from facts.

Sources

Brand ownership and serial format verified against the InterNACHI water heater dating chart and the A.O. Smith corporate brands page.

Frequently asked questions

Who makes Envirotemp water heaters?
Envirotemp is one of the private-label trade names built by U.S. Craftmaster / American Water Heater, the A.O. Smith family of manufacturers. The InterNACHI water heater dating chart lists Envirotemp among the dozens of labels produced on A.O. Smith lines, so its serials decode with the same year-week format as State, Reliance, and American units.
How do I tell the age of an Envirotemp water heater from the serial number?
The first two digits of the serial are the year and the next two are the week of manufacture. For example, serial 1007C001224 means week 7 of 2010 — mid-February 2010. Letters before or inside the serial are factory codes; read the date from the leading digits.
Where is the serial number on an Envirotemp water heater?
On the rating plate — a sticker on the side of the tank, usually in the upper half, listing the model and serial numbers together. On units where the label has faded, take a photo and raise the contrast; the first four digits are all you need.
Are Envirotemp and American water heaters the same?
They come from the same production lines. Envirotemp is a trade name of the American Water Heater Company, which was acquired by A.O. Smith in 2001 and now builds State, Reliance, American, U.S. Craftmaster, and the various private labels. All use the same serial date coding.
How long does an Envirotemp water heater last?
Like other tank-style units, about 8–12 years. Regular sediment flushing and anode rod replacement help; hard water shortens the life. If the serial shows the tank is past 10 years, plan for replacement before a leak decides for you.