How old is my Ruud furnace?
Serial number age decoder for Ruud furnaces: 2 format eras, the decode rule in plain English, transcribed tables, and the official lookup.
Type the serial from the data plate, not the model number. Nothing is sent anywhere; the tables are in this page.
Format example: W291013412
- Ruud furnace serial numbers in the era not stated format encode the year as digits 4-5 (YY) and the week as digits 2-3 (source: building-center.org).
- Example: serial W291013412 decodes to week 29 of 2010.
- Ruud furnace serial numbers in the era not stated format encode the year as digits 3-4 after the middle factory letter and the week as digits 1-2 after the middle factory letter (source: building-center.org).
- Example: serial 7351 M2806 16735 decodes to week 28 of 2006.
- Ruud's official lookup at rheem.registermyunit.com returns warranty terms.
Format eras
- era not stated VERIFIED
A#########digits 4-5 (YY) - era not stated VERIFIED
#### A#### #####digits 3-4 after the middle factory letter
How to read the serial
era not stated formatVERIFIED
Shape A######### · example W291013412 · confidence high
- Year
- digits 4-5 (YY)
- Week or month
- week = digits 2-3
- Plant
- letter 1 (e.g. W)
Example: serial W291013412 decodes to week 29 of 2010.
Listed under Rheem in the source; Ruud is named in that format's family and the corporate link is an estimate, not a checked fact.
era not stated formatVERIFIED
Shape #### A#### ##### · example 7351 M2806 16735 / CB5D302F099903346 / OR177 M2807 00097 · confidence high
- Year
- digits 3-4 after the middle factory letter
- Week or month
- week = digits 1-2 after the middle factory letter
- Plant
- middle letter F, M, G, W or N
Example: serial 7351 M2806 16735 decodes to week 28 of 2006.
Listed under Rheem in the source; Ruud is named in that format's family and the corporate link is an estimate, not a checked fact.
Where the data plate is on a furnace
Inside the furnace: remove the upper (burner) access door and look on the inside of the door, on the blower compartment wall, or on a sticker facing you at the burner deck.
General guidance, not brand-specific: the owner's manual or the installer can point to the exact spot. See the data plate guide.
For scale only: the InterNACHI Standard Estimated Life Expectancy Chart for Homes lists Furnace at 15 to 25 years of expected service (nachi.org). That chart is a guideline, not a prediction for your unit.
Open the official Ruud lookup takes serial; returns warranty terms; URL unverified
This site is a reference built from published tables. The manufacturer's own lookup wins whenever the two disagree.
What we could not confirm
- Ruud is treated as sharing Rheem's format because the source lists it in that family; the corporate relationship itself is an estimate.
- Rheem acquired Ruud in 1959 (building-center). Ruud page lists the identical six Rheem HVAC styles (W291013412; CB5D302F099903346; 7351 M2806 16735; OR177 M2807 00097; 0804B10488 MMYY; 123451872) with the same chart images (Rheem-HVAC-style-1..6). ruud.com is (c) Rheem Manufacturing Company and ruud.com/warranties 404s; the lookup lives on Rheem's registermyunit portal (curl 200). Water-heater page: https://www.building-center.org/ruud-water-heater-age/ (not fetched this batch).