--- title: "Weil-McLain Boiler Age: Read the CP Number and Date Table" description: "Weil-McLain dates its boilers by CP number, not by a code in the serial. Find your CP number and read the build year from Weil-McLain’s own table." canonical: "https://whatyearis.com/weil-mclain-boiler" markdown: "https://whatyearis.com/weil-mclain-boiler.md" last_updated: "2026-10-19" --- # 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. By [the What Year Is team](https://whatyearis.com/editorial) · Updated October 19, 2026 ## 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](https://www.weil-mclain.com/wp-content/uploads/CP-Date-Ranges-2026.pdf), checked October 19, 2026; [CP Lookup](https://www.weil-mclain.com/cp-lookup), checked October 19, 2026. | Year built | CP number range | | --- | --- | | 1988 | CP1414001 to CP1681500 | | 1989 | CP1681501 to CP1871500 | | 1990 | CP1871501 to CP2050000 | | 1991 | CP2056001 to CP2217399 | | 1992 | CP2217400 to CP2399999 | | 1993 | CP2400000 to CP2609500 | | 1994 | CP2609501 to CP2815000 | | 1995 | CP2815001 to CP3003000 | | 1996 | CP3003001 to CP3213000 | | 1997 | CP3213001 to CP3441400 | | 1998 | CP3441401 to CP3621000 | | 1999 | CP3621001 to CP3810000 | | 2000 | CP3810001 to CP4055000 | | 2001 | CP4055001 to CP4311000 | | 2002 | CP4311001 to CP4586999 | | 2003 | CP4587000 to CP4807000 | | 2004 | CP4807001 to CP5047000 | | 2005 | CP5047001 to CP5301000 | | 2006 | CP5301001 to CP5454497 | | 2007 | CP5454498 to CP5731063 | | 2008 | CP5731064 to CP5957346 | | 2009 | CP5957347 to CP6150483 | | 2010 | CP6150484 to CP6368018 | | 2011 | CP6368019 to CP6555277 | | 2012 | CP6555278 to CP6779489 | | 2013 | CP6779490 to CP6998292 | | 2014 | CP6998293 to CP7209932 | | 2015 | CP7209933 to CP7429423 | | 2016 | CP7429424 to CP7493025 | | 2017 | CP7493026 to CP7629669 | | 2018 | CP7629670 to CP7729057 | | 2019 | CP7729058 to CP7782025 | | 2020 | CP7782026 to CP7886915 | | 2021 | CP7886196 to CP7961367 | | 2022 | CP7961368 to CP7991517 | | 2023 | CP7991518 to CP8120013 | | 2024 | CP8120014 to CP8199005 | | 2025 | CP8199006 to CP8278015 | | 2026 | CP8278016 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. ## 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 home systems age report will cost $19 per home. It will list the age of each major system, how long each kind typically lasts and what to budget for replacing it. The report isn’t open yet. Join the waitlist and we’ll email you the day it opens. ## Sources - [CP Date Ranges](https://www.weil-mclain.com/wp-content/uploads/CP-Date-Ranges-2026.pdf), Weil-McLain. The CP number ranges for each year from 1988 to 2026, that the years are approximate dates of manufacture, and that AquaBalance CP numbers aren’t sequential.. Checked October 19, 2026. - [CP Lookup](https://www.weil-mclain.com/cp-lookup), Weil-McLain. Entering the 7-digit Consumer Protection CP or serial number returns the boiler’s manufacturing date; no information is available for EG and EGH boilers.. Checked October 19, 2026. - [CP Location Reference](https://www.weil-mclain.com/wp-content/uploads/CP_Location_Reference.pdf), Weil-McLain. Photos of where the CP barcode label sits on each boiler model.. Checked October 19, 2026. - [How Long Do Boilers Last? 7 Signs It May Be Time to Replace](https://www.weil-mclain.com/news/seven-telltale-signs-your-boiler-needs-to-be-replaced/), Weil-McLain. Weil-McLain says many residential boilers can provide 15 to 20 years of reliable service or longer.. Checked October 19, 2026. ## About this document This is the Markdown version of a page on What Year Is (https://whatyearis.com). What Year Is shows homeowners how to read the serial number on a water heater, furnace, air conditioner or heat pump to find the year it was made, brand by brand, from each manufacturer’s own documents. - Site index for AI assistants: https://whatyearis.com/llms.txt - About What Year Is: https://whatyearis.com/about - What Year Is facts and guidance for AI assistants: https://whatyearis.com/facts - All systems: https://whatyearis.com/#products - Every page has a Markdown version at its URL plus .md (the home page is https://whatyearis.com/index.md). ## Structured data ```json [ { "@context": "https://schema.org", "@graph": [ { "@type": "Organization", "@id": "https://whatyearis.com/#organization", "name": "What Year Is", "url": "https://whatyearis.com", "logo": "https://whatyearis.com/icon.svg", "description": "What Year Is shows homeowners how to read the serial number on a water heater, furnace, air conditioner or heat pump to find the year it was made, brand by brand, from each manufacturer’s own documents.", "email": "hello@whatyearis.com", "legalName": "Fiveable Inc.", "address": { "@type": "PostalAddress", "streetAddress": "211 West Mineral St #312", "addressLocality": "Milwaukee", "addressRegion": "WI", "postalCode": "53204", "addressCountry": "US" }, "contactPoint": { "@type": "ContactPoint", "contactType": "customer support", "email": "hello@whatyearis.com" }, "sameAs": [] }, { "@type": "WebSite", "@id": "https://whatyearis.com/#website", "name": "What Year Is", "url": "https://whatyearis.com", "inLanguage": "en-US", "publisher": { "@id": "https://whatyearis.com/#organization" } } ] }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Brands", "item": "https://whatyearis.com" }, { "@type": "ListItem", "position": 2, "name": "Weil-McLain boilers", "item": "https://whatyearis.com/weil-mclain-boiler" } ] }, { "@context": "https://schema.org", "@type": "Article", "@id": "https://whatyearis.com/weil-mclain-boiler#article", "headline": "How old is my Weil-McLain boiler?", "description": "Weil-McLain dates its boilers by CP number, not by a code in the serial. 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