HVAC Serial Number Lookup
WeatherKing Serial Number Lookup
WeatherKing is part of the Rheem family, alongside Rheem, Ruud, Sure Comfort. Enter the serial from the data plate below to get the manufacture date with a character-by-character explanation, the unit's age, its refrigerant era, and the warranty picture.
Decode schemes compiled from manufacturer literature and inspector references, cross-checked across two sources wherever possible (WeatherKing sources: building-center.org + pickhvac; pickhvac (week reading) vs building-center.org (month reading); both agree on the year). Single-sourced rules are labeled low confidence instead of being presented as fact. A date stamped or printed on the data plate always outranks a serial decode.
WeatherKing Serial Number Formats
| Format | Era | Example | Confidence |
|---|---|---|---|
| Letter + 9 digits; digits 2-3 = week, digits 4-5 = year (Rheem encodes week + year, never month) | ~1990s to present | W291013412 = week 29 of 2010 (mid-July) | high |
| 4 digits + letter + 5 digits; digits 3-4 = year. Sources conflict on whether digits 1-2 are the week or the month | older units; also seen on water heaters | 0902C11246 = 2002; week 9 or September depending on the reading | medium |
| 13+ characters with a factory letter (F, M, G, W, or N) mid-serial; the four digits after it are week then year | package/commercial and older spaced formats | AB7E203M129703576 = week 12 of 1997 | medium |
| 9 digits; the last two are the year, the two before them the week | mid-1970s and earlier | 168252873 = week 28 of 1973 | medium |
Worked Example: WeatherKing W291013412
Expected decode: week 29 of 2010 (mid-July). Character by character:
W = line/plant letter
29 = week 29 (positions 2-3)
10 = year 2010 (positions 4-5)
13412 = production sequence
WeatherKing Refrigerant Timeline
| Manufacture year | Typical refrigerant | Notes |
|---|---|---|
| through 2009 | R-22 | Standard refrigerant of the era. Production of new R-22 ended in 2020; supply is reclaim-only. |
| 2010 to 2024 | R-410A | EPA banned R-22 in new equipment from January 1, 2010; R-410A was the standard through 2024. |
| 2025 and later | R-454B | Rheem and Ruud residential moved to R-454B from January 2025. During the mid-2025 R-454B cylinder shortage Rheem temporarily raised factory pre-charge on 13.4/14.3 SEER2 units to cover 30-foot line sets. |
The refrigerant printed on the nameplate is authoritative; this timeline tells you what is typical for the age, not what is in a specific unit.
WeatherKing Warranty Baseline
Current policy: 10-year conditional parts warranty on eligible residential models registered within 60 days at RegisterMyUnit.com (original owner, residential application); 5-year parts unregistered on most lines. Value lines like Sure Comfort may carry shorter base terms.
Source: rheem.com/warranties. Decode the manufacture date above, then confirm coverage through the manufacturer's own serial-number warranty lookup.
Frequently Asked Questions
How old is my WeatherKing unit?
Decode the serial number from the data plate. The dominant WeatherKing format (~1990s to present) is: Letter + 9 digits; digits 2-3 = week, digits 4-5 = year (Rheem encodes week + year, never month). Example: W291013412 decodes to week 29 of 2010 (mid-July). Subtract the decoded year from the current year for the age. Units past 15 years are replacement candidates, and past 20 a major repair rarely pays off.
Which brands share the WeatherKing serial number format?
WeatherKing is part of the Rheem family, alongside Rheem, Ruud, and Sure Comfort. These brands come off shared production lines with the same data plates, so one decode rule dates all of them, and the refrigerant and warranty picture is the same across the family.
What refrigerant does a WeatherKing unit use?
By manufacture year: through 2009: R-22; 2010 to 2024: R-410A; 2025 and later: R-454B. The refrigerant printed on the nameplate is authoritative; the year-based mapping tells you what is typical for the age, not what is in a specific unit.
Is my WeatherKing unit still under warranty?
Current policy: 10-year conditional parts warranty on eligible residential models registered within 60 days at RegisterMyUnit.com (original owner, residential application); 5-year parts unregistered on most lines. Value lines like Sure Comfort may carry shorter base terms. Decode the manufacture date above, then confirm coverage by running the full serial through the manufacturer's own warranty lookup. Terms shown are the current policy; older units often carried different terms.
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