--- title: "How Old Is My Water Heater, Furnace or AC? | What Year Is" description: "Read the serial number on your water heater, furnace or air conditioner and find the year it was made, brand by brand, with worked examples." canonical: "https://whatyearis.com" markdown: "https://whatyearis.com/index.md" last_updated: "2026-10-19" --- # How old is your water heater, furnace or AC? Most water heaters, furnaces and air conditioners hide their build date in the serial number on the rating plate. Each manufacturer uses its own code, so pick your brand below and we’ll show you how to read it, digit by digit, with worked examples from the manufacturer’s own documents. We’re also building a home systems age report that puts every system’s age, typical life and replacement budget in one place. What Year Is isn’t affiliated with any manufacturer. Brand names describe which labels each page covers. ## What are you trying to date? Pick the brand on the rating plate. Brands made in the same factory often share a page because they share a serial format. ### Water heaters - [Bradford White water heaters](https://whatyearis.com/bradford-white-water-heater) - [A.O. Smith water heaters](https://whatyearis.com/ao-smith-water-heater) - [Lochinvar water heaters and boilers](https://whatyearis.com/lochinvar-water-heater) ### Furnaces, air conditioners and heat pumps - [Goodman and Amana furnaces](https://whatyearis.com/goodman-furnace) - [Goodman and Amana air conditioners and heat pumps](https://whatyearis.com/goodman-ac) - [Carrier and Bryant air conditioners and heat pumps](https://whatyearis.com/carrier-ac) - [Lennox furnaces](https://whatyearis.com/lennox-furnace) - [Lennox air conditioners and heat pumps](https://whatyearis.com/lennox-ac) - [Daikin air conditioners and heat pumps](https://whatyearis.com/daikin-ac) ### Boilers - [Weil-McLain boilers](https://whatyearis.com/weil-mclain-boiler) ## What will the home systems age report include? The home systems age report will list the age of each major system in your home from its serial number, how long each kind of system typically lasts, and what to budget for replacing each one over the next ten years, on one page you can keep. ## 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. ## Common questions ### Is the report a subscription? No. The report will be paid for once, per home, and nothing renews. ### Where is the serial number on a water heater or furnace? On the rating plate. On a tank water heater it’s a label on the side of the tank. On a furnace it’s usually inside the front panel, and on an outdoor AC or heat pump it’s on a side panel. Each brand page says where that manufacturer puts it. ### What if my label doesn’t match any format here? Some older units used formats the manufacturer no longer documents. The manufacturer’s customer service line can usually date a unit from its model and serial number. ## 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": "FAQPage", "url": "https://whatyearis.com", "mainEntity": [ { "@type": "Question", "name": "Is the report a subscription?", "acceptedAnswer": { "@type": "Answer", "text": "No. The report will be paid for once, per home, and nothing renews." } }, { "@type": "Question", "name": "Where is the serial number on a water heater or furnace?", "acceptedAnswer": { "@type": "Answer", "text": "On the rating plate. On a tank water heater it’s a label on the side of the tank. On a furnace it’s usually inside the front panel, and on an outdoor AC or heat pump it’s on a side panel. Each brand page says where that manufacturer puts it." } }, { "@type": "Question", "name": "What if my label doesn’t match any format here?", "acceptedAnswer": { "@type": "Answer", "text": "Some older units used formats the manufacturer no longer documents. The manufacturer’s customer service line can usually date a unit from its model and serial number." } } ] } ] ```