How old is my unit
Home / Brands / A.O. Smith / Heat Pump Water Heater

How old is my A.O. Smith heat pump water heater?

Serial number age decoder for A.O. Smith heat pump water heaters: 1 format era, the decode rule in plain English, transcribed tables, and the official lookup.

Serial number decoder for A.O. Smith heat pump water heater

Type the serial from the data plate, not the model number. Nothing is sent anywhere; the tables are in this page.

Format example: 1210A002243

Format eras

How to read the serial

2008 to present formatVERIFIED

Shape ####A###### · example 1210A002243 / S1318 F000046 / 1836111786352 · confidence high

Year
digits 1-2 (YY) after optional leading S
Week or month
week = digits 3-4
Plant
letter after the 4 date digits (unpublished)

Example: serial 1210A002243 decodes to week 10 of 2012.

Trap: Sub-brand applicability (State/American/Reliance/Whirlpool/Kenmore) is ESTIMATE: building-center a-o-smith page covers AO Smith; each sub-brand has its own page to fetch in fan-out. Century: 20YY only for this style.

Where the data plate is on a heat pump water heater

On the tank side like a conventional heater, usually below the compressor housing.

General guidance, not brand-specific: the owner's manual or the installer can point to the exact spot. See the data plate guide.

Official lookup: the authority

Open the official A.O. Smith lookup takes serial or reference number; returns warranty status; URL verified live

This site is a reference built from published tables. The manufacturer's own lookup wins whenever the two disagree.

Sources

Frequently asked questions

How do I tell the age of a A.O. Smith heat pump water heater from the serial number?

In the 2008 to present format the year is digits 1-2 (YY) after optional leading S and the week as digits 3-4. Example: serial 1210A002243 decodes to week 10 of 2012.

Where is the serial number on a A.O. Smith heat pump water heater?

On the data plate. On the tank side like a conventional heater, usually below the compressor housing.