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)Cand 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.