How old is my Weil-McLain unit?
Weil-McLain is part of SPX / Marley. 1 serial format sourced across boiler.
- Weil-McLain's official lookup at weil-mclain.com returns warranty / registration lookup.
Official lookup: the authority
Open the official Weil-McLain 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.
Decoder pages by product
Format eras
- 1988 to present VERIFIED
AA #######Boiler
What we could not confirm
- The 1988 to present format is documented but not decodable here: year position not parseable from prose: 'range lookup on the CP number (table)'.
- Date is NOT in the serial: it is the consecutive 7-digit 'CP' number on a separate tag. Official CP Lookup returns the manufacturing date (boilers only; EG/EGH not available; 6-digit numbers: prefix a zero, e.g. CP0123456). AquaBalance CP numbers are not sequential.
Sources
- https://www.building-center.org/weil-mclain-hvac-age/
- img: Weil-McLain-CP-Chart.jpg
- https://www.weil-mclain.com/cp-lookup/official