How old is my Takagi unit?
Takagi is part of A.O. Smith Corp. 6 serial formats sourced across water heater, tankless water heater.
Serial number decoder for Takagi
Type the serial from the data plate, not the model number. Nothing is sent anywhere; the tables are in this page.
Format example: 1544E000453
- Takagi water heater serial numbers in the 2010 to present format encode the year as digits 1-2 (20YY) and the week as digits 3-4 (source: building-center.org).
- Example: serial 1544E000453 decodes to week 44 of 2015.
- Takagi water heater serial numbers in the 2008 to present format encode the year as digits 1-2 (YY) after optional leading S and the week as digits 3-4 (source: building-center.org).
- Example: serial 1210A002243 decodes to week 10 of 2012.
- Takagi's official lookup at takagi.com returns warranty / registration lookup.
Decoder pages by product
Format eras
- 2010 to present VERIFIED
####A######Tankless Water Heater - before 2010 VERIFIED
A##A######Water Heater - before 2009 VERIFIED
########Tankless Water Heater - 2008 to present VERIFIED
####A######Water Heater, Heat Pump Water Heater, Tankless Water Heater - before 2008 VERIFIED
AA##A######Water Heater - 1970 to 1979 VERIFIED
A##-A-##-######Water Heater
Official lookup: the authority
Open the official Takagi lookup takes serial number; returns warranty / registration lookup; URL verified live
This site is a reference built from published tables. The manufacturer's own lookup wins whenever the two disagree.
What we could not confirm
- The before 2009 format is documented but not decodable here: no year decode text.
- Takagi is treated as sharing A.O. Smith's format because the source lists it in that family; the corporate relationship itself is an estimate.
- Post-2009 serials are AO Smith YYWW; pre-2009 8-digit serials are sequential with no date.