HVAC Decoder
Amana Tonnage From Model Number
Where Amana puts the capacity code, what each code means, and the readings that look like capacity but are not. Read out of 3 documents Amana publishes itself, named further down with the date each was fetched.
Starting the decoder. The capacity tables below this box are already loaded, so you can read your code off them now.
Nominal capacity from a model number is a nameplate convention, not a measurement. Actual delivered capacity depends on the matched indoor unit, line set, airflow and conditions. Confirm against the data plate's BTU/h rating and the AHRI certificate for the matched system.
Amana Capacity Codes and Tonnage
R-410A ASX and ASZ generation
Capacity sits at positions 6-8, the 3 digit group after the SEER digits. Example: ASX140361KA.
| Code | Nominal BTU/h | Tons | Code / 12 |
|---|---|---|---|
| 018 | 18,000 | 1.5 | same answer |
| 019 | 18,000 | 1.5 | 1.58, so the division is wrong here |
| 024 | 24,000 | 2 | same answer |
| 025 | 24,000 | 2 | 2.08, so the division is wrong here |
| 030 | 30,000 | 2.5 | same answer |
| 031 | 30,000 | 2.5 | 2.58, so the division is wrong here |
| 036 | 36,000 | 3 | same answer |
| 037 | 36,000 | 3 | 3.08, so the division is wrong here |
| 042 | 42,000 | 3.5 | same answer |
| 043 | 42,000 | 3.5 | 3.58, so the division is wrong here |
| 048 | 48,000 | 4 | same answer |
| 060 | 60,000 | 5 | same answer |
Table transcribed from Product Specifications SS-ASX14 (SS-ASX14), fetched from amana-hac.com on 2026-07-24.
Current R-410A ASXS S-series
Capacity sits at positions 7-8, which is a different place from the equivalent Goodman generation, and one position further along than the older Amana layout. Example: ASXS6S3610A.
| Code | Nominal BTU/h | Tons | Code / 12 |
|---|---|---|---|
| 18 | 18,000 | 1.5 | same answer |
| 24 | 24,000 | 2 | same answer |
| 30 | 30,000 | 2.5 | same answer |
| 36 | 36,000 | 3 | same answer |
| 42 | 42,000 | 3.5 | same answer |
| 48 | 48,000 | 4 | same answer |
| 60 | 60,000 | 5 | same answer |
Table transcribed from Product Specifications SS-ASXS6 (SS-ASXS6, 09/24, supersedes 09/23), fetched from amana-hac.com on 2026-07-24.
R-32 ALXS and ALZS scroll line
Capacity sits at positions 8-9, the same place as the Goodman R-32 line, because the two brands share this document template. Position 2 is L for the R-32 split system line. Example: ALXS4BA3610AA.
| Code | Nominal BTU/h | Tons | Code / 12 |
|---|---|---|---|
| 18 | 18,000 | 1.5 | same answer |
| 24 | 24,000 | 2 | same answer |
| 30 | 30,000 | 2.5 | same answer |
| 36 | 36,000 | 3 | same answer |
| 42 | 42,000 | 3.5 | same answer |
| 48 | 48,000 | 4 | same answer |
| 60 | 60,000 | 5 | same answer |
Table transcribed from Product Specifications SS-ALXS5B-R32 (SS-ALXS5B-R32, 01/26, supersedes 08/24), fetched from amana-hac.com on 2026-07-24.
The Amana codes that dividing by 12 gets wrong
The usual shortcut is that a capacity code is the nominal BTU/h divided by 1,000, so dividing it by 12 gives the tonnage. Amana prints 5 codes where that arithmetic disagrees with Amana's own table, and the table is what the equipment is sold against:
| Code | Amana prints | Code / 12 gives |
|---|---|---|
| 019 | 1.5 tons | 1.58 |
| 025 | 2 tons | 2.08 |
| 031 | 2.5 tons | 2.58 |
| 037 | 3 tons | 3.08 |
| 043 | 3.5 tons | 3.58 |
These are not derivable, only transcribable, which is why this decoder carries Amana's printed table rather than a formula. If you meet one of these codes in the field, arithmetic will land you between two real sizes, and the printed table is the only thing that resolves it.
Worked example: Amana ASX140361KA
Capacity code 036 at characters 6-8 of ASX140361KA: 36,000 BTU/h, which is 3 tons at 12,000 BTU/h per ton. Positions 6-8 are the capacity code in the Goodman/Amana split layout.
- Efficiency: 14 SEER. Positions 4-5 are the SEER rating (ASX14).
- Refrigerant: R-410A. Amana position 3 "X Condenser R-410A" per SS-ASX14.
- Product type: AC condenser. Position 3 unit type X.
Amana has 3 documented layouts: R-410A ASX and ASZ generation reads capacity at positions 6-8; Current R-410A ASXS S-series reads capacity at positions 7-8; R-32 ALXS and ALZS scroll line reads capacity at positions 8-9. They put the capacity in different places, so a rule written for one and applied to the other is how a right-looking number ends up under the wrong heading.
What is specific to Amana
Models this decoder refuses rather than guesses
An undocumented code publishes nothing. Each of these would produce a plausible number by general arithmetic, and the decoder returns no match instead, because no Amana document supports it.
| Model | What the decoder returns | Why |
|---|---|---|
| ASX140091KA | no match | 009 is on the universal ladder but is in no Amana capacity table. |
| ASXS6S0910A | no match | The mini-split classes 09, 12 and 15 sit on the tool's shared ladder but appear in no Amana ducted capacity table, so they publish nothing on a ducted Amana model. |
The Amana documents behind this page
Fetched from amana-hac.com on 2026-07-24. Covers the R-410A ASX generation, independently of any Goodman document, corroborated inside itself by its Product Specifications rated-BTU/h table.
Fetched from amana-hac.com on 2026-07-24. Covers the current R-410A ASXS layout, whose worked model is numbered positions 1 to 12, whose Tonnage Nominal sits at positions 7-8, and whose position 2 reads Split System R-410A.
Fetched from amana-hac.com on 2026-07-24. Covers the R-32 ALXS and ALZS layout: a worked model numbered across positions 1 to 13, position 1 A for Amana Brand, position 2 L for R-32 Splits System, and Nominal Capacity at positions 8-9. This is the document a prior session concluded did not exist.
Frequently asked questions
How do I find the tonnage of an Amana unit from the model number?
Read the capacity code: on Amana it sits at positions 6-8, the 3 digit group after the SEER digits. On ASX140361KA that code is 036, which is 36,000 BTU/h, or 3 tons, because one ton of cooling is 12,000 BTU/h. Use the OUTDOOR unit's model number for system cooling capacity; the indoor air handler or coil carries its own number. This position comes from Amana's own SS-ASX14, not from a third-party chart.
Can I just divide the Amana capacity code by 12?
Not on every code. Amana prints 5 capacity codes where that division gives the wrong answer: 019 is 1.5 tons where dividing gives 1.58, 025 is 2 tons where dividing gives 2.08, 031 is 2.5 tons where dividing gives 2.58, 037 is 3 tons where dividing gives 3.08, 043 is 3.5 tons where dividing gives 3.58. Those values come from Amana's own printed table rather than from arithmetic, which is the whole reason the table exists. On every other code in the table the division does work.
Where is the model number on an Amana unit?
On the data plate on the outdoor unit. On the current side-discharge cabinets it faces the same way as the service pane. It is labeled M/N, MODEL or MODEL NO., usually printed directly above or beside the serial number. The model number describes what the unit is, including its capacity. The serial number describes when it was built and carries no capacity information at all.
Which Amana document is this based on?
Product Specifications SS-ASX14 (SS-ASX14), fetched from amana-hac.com on 2026-07-24, which covers the R-410A ASX generation, independently of any Goodman document, corroborated inside itself by its Product Specifications rated-BTU/h table. Product Specifications SS-ASXS6 (SS-ASXS6, 09/24, supersedes 09/23), fetched from amana-hac.com on 2026-07-24, which covers the current R-410A ASXS layout, whose worked model is numbered positions 1 to 12, whose Tonnage Nominal sits at positions 7-8, and whose position 2 reads Split System R-410A. Product Specifications SS-ALXS5B-R32 (SS-ALXS5B-R32, 01/26, supersedes 08/24), fetched from amana-hac.com on 2026-07-24, which covers the R-32 ALXS and ALZS layout: a worked model numbered across positions 1 to 13, position 1 A for Amana Brand, position 2 L for R-32 Splits System, and Nominal Capacity at positions 8-9. This is the document a prior session concluded did not exist. Every capacity value on this page traces to one of those documents, and each is named with the date it was fetched so you can pull it yourself.
Is the decoded tonnage the size I should install?
No. Nominal tonnage is what the unit was built to deliver, not what the building needs, and the old unit may have been oversized or sized before insulation and window changes. Treat it as a starting clue and run a load calculation before matching a replacement. Actual delivered capacity also depends on the matched indoor unit, line set, airflow and conditions.
Related tools
Tonnage From Model Number (all brands)
The full decoder: 40+ brands, the universal capacity ladder, and the brands whose own tables override it.
Amana Serial Number Lookup
The model number gives the size. The serial gives the age and the refrigerant era. Decode Amana build dates.
BTU / HVAC Load Calculator
Size the actual load by climate zone, insulation and windows, then check it against the decoded nominal tonnage.
MCA / MOCP Breaker & Wire Size
Got the size? Size the circuit next: nameplate MCA and MOCP to wire, breaker and ground per NEC Article 440.
Other brands with their own manufacturer nomenclature document: Carrier tonnage by model number, Trane tonnage by model number, Lennox tonnage by model number, Goodman tonnage by model number.
Got the tonnage? Check it against the actual load.
The old unit's nominal size is a clue, not a load calculation. Oversized systems short-cycle and dehumidify poorly. Run the numbers before you match a replacement.