Brands / Weil-McLain boilers

How old is my Weil-McLain boiler?

A Weil-McLain boiler’s build date isn’t coded into its serial. Instead, each boiler has a CP number, CP followed by seven digits, printed on a barcode sticker. Weil-McLain’s CP Lookup tool returns the build date for most boilers, and its CP date table gives the year for numbers from 1988 on. A boiler with CP7700000 falls in the 2018 range.

Which year does my Weil-McLain CP number fall in?

Find the range your CP number falls in, then read the year on the left. Weil-McLain calls these approximate dates of manufacture. Its table says AquaBalance CP numbers aren’t sequential, so the table may not work for that model, and its CP Lookup has no data for EG and EGH boilers.

Sources: CP Date Ranges, checked October 19, 2026; CP Lookup, checked October 19, 2026.
Year builtCP number range
1988CP1414001 to CP1681500
1989CP1681501 to CP1871500
1990CP1871501 to CP2050000
1991CP2056001 to CP2217399
1992CP2217400 to CP2399999
1993CP2400000 to CP2609500
1994CP2609501 to CP2815000
1995CP2815001 to CP3003000
1996CP3003001 to CP3213000
1997CP3213001 to CP3441400
1998CP3441401 to CP3621000
1999CP3621001 to CP3810000
2000CP3810001 to CP4055000
2001CP4055001 to CP4311000
2002CP4311001 to CP4586999
2003CP4587000 to CP4807000
2004CP4807001 to CP5047000
2005CP5047001 to CP5301000
2006CP5301001 to CP5454497
2007CP5454498 to CP5731063
2008CP5731064 to CP5957346
2009CP5957347 to CP6150483
2010CP6150484 to CP6368018
2011CP6368019 to CP6555277
2012CP6555278 to CP6779489
2013CP6779490 to CP6998292
2014CP6998293 to CP7209932
2015CP7209933 to CP7429423
2016CP7429424 to CP7493025
2017CP7493026 to CP7629669
2018CP7629670 to CP7729057
2019CP7729058 to CP7782025
2020CP7782026 to CP7886915
2021CP7886196 to CP7961367
2022CP7961368 to CP7991517
2023CP7991518 to CP8120013
2024CP8120014 to CP8199005
2025CP8199006 to CP8278015
2026CP8278016 and up

What will the home systems age report add?

The home systems age report will put your Weil-McLain boiler next to every other major system in your home, each with its build year, how long that kind of system typically lasts, and what to budget for replacing it.

Get the home systems age report

We’ll email you once, the day the report opens.

We’re building a home systems age report: your Weil-McLain boiler and every other major system, each with its age, typical life and replacement budget.

Where is the CP number on a Weil-McLain boiler?

The CP number is on a barcode sticker on the boiler’s jacket. Where it sits depends on the model: Weil-McLain’s CP Location Reference has a photo for each one, and on several models the sticker is near the rating plate on the side of the jacket. Some models also have one inside the front jacket panel.

What do some Weil-McLain CP numbers decode to?

These are made up to show how the table works and don’t belong to real boilers.

CP number Range it falls in Year built
CP7700000 CP7629670 to CP7729057 2018
CP5600000 CP5454498 to CP5731063 2007
CP3100000 CP3003001 to CP3213000 1996
CP8250000 CP8199006 to CP8278015 2025

How long do Weil-McLain boilers last?

Weil-McLain says many residential boilers can provide 15 to 20 years of reliable service or longer. A boiler’s life depends a lot on its water, its installation and how it’s been maintained, so the build year is a starting point.

Common questions about Weil-McLain boiler serial numbers

My CP number has only six digits. What do I do?

Weil-McLain’s lookup asks for seven digits, so add a zero after CP. CP123456 becomes CP0123456. Numbers that low come before 1988, which is where the table starts, so the lookup tool or Weil-McLain’s warranty department is the way to date them.

Why do the 2020 and 2021 ranges overlap?

Weil-McLain’s table, as published, starts 2021 at CP7886196, which is below the end of the 2020 range at CP7886915. If your number falls between those two, the boiler was built in 2020 or 2021, and the CP Lookup tool can settle it.

Why is there a gap between 1990 and 1991?

Weil-McLain’s table ends 1990 at CP2050000 and starts 1991 at CP2056001. If your number falls between CP2050001 and CP2056000, the boiler was most likely built in 1990 or 1991, and the CP Lookup tool or Weil-McLain’s warranty department can settle it.

Is the CP number the same as the serial number?

Weil-McLain’s lookup calls it the Consumer Protection CP or serial number. It’s the seven-digit number after CP on the barcode sticker.

What will the home systems age report cost?

The report isn’t open yet. The button adds you to the waitlist, and we’ll email you the day it opens.