Goodman AC unit age by serial number (also Amana and Daikin)
Goodman, Amana and Daikin serial numbers are ten digits, and for most products the first four are the year and the month of manufacture: a serial beginning 1306 was made in June 2013. The rule is printed in the warranty certificates of all three brands, and the decoder repeats the manufacturer's "for most products" caveat with every result.
Where the serial number is
The rating plate of an outdoor unit is on the cabinet; a furnace plate is inside the cabinet. Inside a furnace you may also find a label on the control board with its own date code. That date belongs to the board, not to the furnace, and is not the unit's serial number.
Year first, then the calendar month
Carrier, Bryant, Trane and Rheem count production weeks. Goodman, Amana and Daikin print the calendar month instead, so a decoded date is exact to the month. 2610 is October 2026, the example in the newest certificates, and 0807 is July 2008.
Which century, and the "most products" caveat
The certificates give only two year digits and do not say when the layout started. We read them as 2000 or later and report a serial that would fall in the 1990s as not confirmed, rather than assume that older units followed the same rule. The manufacturer also does not list which products are the exceptions to "most products", so a quick check against the installation paperwork is worthwhile.
Model numbers
Goodman GSX and GSZ models carry the capacity in characters 6 to 8 (GSX140361 is 036, or 3 tons); X is an R-410A air conditioner and Z an R-410A heat pump. Newer SEER2 models such as GSXH503610 move the size to characters 7 and 8. R-32 models are marked with L, as in GLXS4BA3610AA and the Amana ALXS line, where the size sits in characters 8 and 9. Daikin DZ14SA0363AA is an R-410A heat pump of 3 tons.
For Goodman and Amana gas furnaces such as GMVC960804CN, the input code 080 stands for 80,000 BTU/h.
How to read the plate, step by step
- Type the ten digits from the rating plate.
- The first two digits are the year, the next two the month.
- Pick the brand and add the model number for the nominal size and the refrigerant code.
- If the date clashes with what you know about the installation, treat the serial as an exception to the rule.
Serial formats the decoder reads
| Format | How it is read |
|---|---|
| Goodman/Amana/Daikin year + month (YYMM) | Goodman, Amana and Daikin: the serial is a ten-digit code, and for most products the first four digits are the year (YY) and the month (MM), as the warranty certificates of all three brands state. |
Model number codes the decoder reads
Only the codes listed here are translated. A code outside this list is shown as "not in the table", and you read the size or input from the plate instead.
| Nomenclature | Position | Codes |
|---|---|---|
| Goodman GSX / GSZ (R-410A) | Goodman GSX and GSZ models such as GSX140361: X is an R-410A condenser and Z an R-410A heat pump; characters 6-8 are the nominal capacity in thousands of BTU/h (036 = 3 tons). | 018 = 1.5 tons, 024 = 2 tons, 030 = 2.5 tons, 036 = 3 tons, 042 = 3.5 tons, 048 = 4 tons, 060 = 5 tons |
| Goodman SEER2 split system (R-410A) | Goodman SEER2 models such as GSXH503610: S means an R-410A split system and characters 7-8 are the nominal capacity in thousands of BTU/h (36 = 3 tons). | 18 = 1.5 tons, 24 = 2 tons, 30 = 2.5 tons, 36 = 3 tons, 42 = 3.5 tons, 48 = 4 tons, 60 = 5 tons |
| Goodman GLXS / Amana ALXS (R-32) | Goodman GLXS and Amana ALXS models such as GLXS4BA3610AA: L means an R-32 split system and characters 8-9 are the nominal capacity in thousands of BTU/h (36 = 3 tons). | 18 = 1.5 tons, 24 = 2 tons, 30 = 2.5 tons, 36 = 3 tons, 42 = 3.5 tons, 48 = 4 tons, 60 = 5 tons |
| Amana ASX (R-410A) | Amana ASX models such as ASX140361: characters 6-8 are the nominal capacity in thousands of BTU/h (036 = 3 tons). | 018 = 1.5 tons, 024 = 2 tons, 030 = 2.5 tons, 036 = 3 tons, 042 = 3.5 tons, 048 = 4 tons, 060 = 5 tons |
| Daikin DZ heat pump (R-410A) | Daikin DZ models such as DZ14SA0363AA: Z is an R-410A heat pump and characters 7-9 are the nominal capacity in thousands of BTU/h (036 = 3 tons). | 018 = 1.5 tons, 024 = 2 tons, 030 = 2.5 tons, 036 = 3 tons, 042 = 3.5 tons, 048 = 4 tons, 060 = 5 tons |
| Daikin DX9VC | Daikin DX9VC models such as DX9VCA3610AA: characters 7-8 are the nominal capacity in thousands of BTU/h (36 = 3 tons). | 18 = 1.5 tons, 24 = 2 tons, 30 = 2.5 tons, 36 = 3 tons, 42 = 3.5 tons, 48 = 4 tons, 60 = 5 tons |
| Goodman/Amana gas furnace | Goodman and Amana gas furnaces such as GMVC960804CN: characters 7-9 are the heating input code in MBTU/h. Our table holds only the codes we transcribed from the manufacturer's sheet. | 080 = 80,000 BTU/h |
Worked examples
Each serial below is either printed in a source or built by us strictly by the source's rule (marked "by the rule"), and each is an automated test of the decoder. Readings that depend on today's date are as of October 27, 2026.
| Serial | Result | Why |
|---|---|---|
| 1306123456Daikinfrom a source | June 2013Decoded | The warranty certificates explain a serial starting 1306 as June 2013 (the last six digits are ours). |
| 2610123456Goodmanfrom a source | October 2026Decoded | The newer certificates use 2610, October 2026. |
| 0807123456Amanaby the rule | July 2008Decoded | Year 08, month 07: July 2008. |
| 9905123456Goodmanby the rule | Not confirmed by the manufacturer | The sources do not say from which year the YYMM layout is used, so 1999 is not given. |
| 1313123456Goodmanby the rule | Does not fit the format | 13 is not a month. |
Edge cases and limits
- We found no R-454B code in any Goodman, Amana or Daikin document we read, so the decoder never infers R-454B from these model numbers.
- Daikin DH5SE (R-32 heat pump) documents disagree on whether the size has two or three digits, so its capacity is not decoded.
- Daikin furnace model numbers such as DM97 and DR96 are not decoded; we have not found their nomenclature.
- A month of 13 or more, or a date later than today, means a typing error or another format.
Questions
How old is my Goodman AC unit?
Read the first four digits of the ten-digit serial number: the first two are the year and the next two the month, so 1306 means June 2013. Amana and Daikin units covered here use the same rule, and the manufacturer says it applies to most products.
What does "for most products" mean for my unit?
The manufacturer does not list the exceptions. If the decoded date clashes with what you know, for example a date after the unit was already in your house, trust the paperwork and treat the serial as another format.
Can I tell the refrigerant from a Goodman model number?
For several lines, yes: X and Z mean R-410A in GSX, GSZ and ASX models, and L means R-32. The refrigerant is also printed on the rating plate.
Related pages
- Nortek (Nordyne) brands: Frigidaire, Gibson and Maytag HVAC units also print a month, after a plant letter.
- Carrier and Bryant: Carrier and Bryant print the week instead of the month.
- Lennox: Lennox uses a month letter after a two-digit plant code.
- All HVAC brand families: Every brand family we decode, and the brands we do not decode yet with the reason.
- Where to find the data plate: Where the serial number sits on each type of equipment and how to copy it without mistakes.
- Refrigerants and EPA dates: Why the date of manufacture alone does not tell you whether a unit uses R-22, R-410A or R-454B.
- Service life estimates: What ENERGY STAR publishes about typical ages, and what kind of number each figure is.
Sources
Every rule on this page comes from the documents below, published by the manufacturer or a U.S. government agency. The date is when we last checked each one.
- Limited warranty certificate PWGACHPR3BODA (serial number note) Goodman Manufacturing Company. Checked .
- How can I confirm the model and serial numbers for my cooling system (FAQ) Goodman Manufacturing Company. Checked .
- Limited warranty certificate PWAACHPR3BODB (serial number note) Goodman Manufacturing Company (Amana brand). Checked .
- Limited warranty PWDACHPHSAC (serial number note) Daikin Comfort Technologies. Checked .
- Furnace limited warranty PWDFURNSNTG (serial number note) Daikin Comfort Technologies. Checked .
- Specification sheet SS-GSX14 Goodman Manufacturing Company. Checked .
- Nomenclature PF-2023 (Goodman) Daikin Comfort Technologies. Checked .
- R-32 nomenclature PF-R32 (Goodman) Goodman Manufacturing Company. Checked .
- R-32 nomenclature PF-R32 (Amana) Goodman Manufacturing Company (Amana brand). Checked .
- Specification sheet SS-ASX14 Goodman Manufacturing Company (Amana brand). Checked .
- Specification sheet SS-DZ14SA Daikin Comfort Technologies. Checked .
- Specification sheet SS-DX9VC Daikin Comfort Technologies. Checked .
- Specification sheet SS-GMVC96 Goodman Manufacturing Company. Checked .