Rheem model number tonnage
On a current Rheem or Ruud air conditioner or heat pump, characters 7 and 8 of the model number give the size in thousands of BTU per hour. Divide by 12 for tons: RA14AY36AJ1NA is 36,000 BTU/h, a 3-ton unit. Rheem gas furnaces carry an input code at characters 6 to 8: R96TA060 is the 60 size.
Decode a Rheem model number
The decoder on this page also reads Ruud model numbers, which follow the same or closely related layouts.
What do the size codes mean?
On an air conditioner or heat pump the code is the nominal cooling capacity in thousands of BTU per hour. One ton of cooling is 12,000 BTU/h, so the code divided by 12 is the tonnage. Some series print the code with a leading zero: 036 and 36 are the same size.
| Code | Nominal BTU/h | Tons | Variant codes in the same size class |
|---|---|---|---|
| 18 or 018 | 18,000 | 1.5 | 17, 19 |
| 24 or 024 | 24,000 | 2 | 25 |
| 30 or 030 | 30,000 | 2.5 | 31 |
| 36 or 036 | 36,000 | 3 | 37, 38 |
| 42 or 042 | 42,000 | 3.5 | 41, 43 |
| 48 or 048 | 48,000 | 4 | 47, 49 |
| 54 or 054 | 54,000 | 4.5 | |
| 60 or 060 | 60,000 | 5 | 59, 61 |
A variant code marks a slightly different version of the same size class. Not every brand uses every code.
On a gas furnace the code is the heating input in thousands of BTU per hour, always three digits: 040 is 40,000 BTU/h, 060 is 60,000, 080 is 80,000, 100 is 100,000 and 120 is 120,000. It is input, not output, and it is not tons.
Where is the tonnage in a Rheem model number?
In the examples, an asterisk stands for a character that varies from one version of the model to the next.
Rheem and Ruud Endeavor Line air conditioners and heat pumps
Characters 7 and 8, right after the refrigerant letter.
RA14AY36AJ1NA reads as 3 tons (36,000 BTU/h nominal).
WA14AY36AJ1N reads as 3 tons (36,000 BTU/h nominal).
The DOE certification database lists it at 33,200 to 34,200 BTU/h of cooling, depending on the indoor unit. More from the same documents: RA14AY18AJ1NA is 1.5 tons (Rheem’s model list calls this the 1 1/2 ton unit); UA18AZ36AJVCA is 3 tons.
| Characters | Meaning |
|---|---|
| 1 | Brand: R = Rheem, U = Ruud |
| 2 | Product: A = air conditioner, P = heat pump |
| 3-4 | SEER2 class |
| 5 | Region: A = all, S = Southeast, N = North |
| 6 | Refrigerant: Y = R-454B, Z = R-410A |
| 7-8 | Capacity: 18 = 18,000 BTU/h to 60 = 60,000 BTU/h |
| 9 | Major series |
| 10 | Voltage: J = 208/230 V, single phase |
| 11 | Type: 1 = single stage, 2 = two stage, V = inverter |
| 12 | Controls: N = non-communicating, C = communicating |
Rheem’s and Ruud’s specification sheets print a “model number identification” legend with the capacity in BTU/h for each code. Numbers that start with W, or have D as the second letter, are not in those sheets; they follow the same layout and were checked against certified ratings. Checked on October 5, 2026: 206 of 206 models in the DOE certification database and 106 of 114 in the ENERGY STAR list read to the certified size.
Where is the size in a Rheem furnace model number?
Rheem R96T and Ruud U96T two-stage gas furnaces
Characters 6 to 8.
R96TA0602317MSA reads as 60,000 BTU/h input.
Rheem’s table rates this model at 56,000 BTU/h high-fire input. More from the same documents: R96TA1152524MSA is 115,000 BTU/h.
| Characters | Meaning |
|---|---|
| 1 | Brand: R = Rheem |
| 2-3 | Series: 96 = 96% efficient |
| 4 | Motor: T = constant torque |
| 5 | Design series |
| 6-8 | Input code: 040 = 42,000 BTU/h, 060 = 56,000, 070 = 70,000, 085 = 84,000, 100 = 98,000, 115 = 112,000 |
| 9 | Stages of heating: 2 = two-stage |
| 10 | Largest air conditioner it can serve: 3 = up to 3 tons, 5 = up to 5 tons |
| 12-13 | Cabinet width: 17 = 17.5 in, 21 = 21 in, 24 = 24.5 in |
Rheem’s R96T specification sheet prints the legend and the rated input for each code. Checked on October 5, 2026: 14 of 14 models in the DOE certification database read to the certified size.
Rheem and Ruud gas furnaces (R95, R97, R98, R80 series and the Ruud equivalents)
Characters 6 to 8.
U97MV0603A17DHSGAP reads as 60,000 BTU/h input.
R921T0603A17M4 reads as 60,000 BTU/h input.
The DOE certification database lists it at 56,000 BTU/h of input. More from the same documents: U97MV1155A24DHSGAP is 115,000 BTU/h.
The digit after the input is not heating capacity. On most series it is the largest air conditioner the blower can serve, in tons.
Ruud’s U97MV specification sheet prints the legend with the heating input at characters 6 to 8 (060 = 60,000 BTU/h to 115 = 115,000). Checked on October 5, 2026: 314 of 314 models in the DOE certification database read to the certified size.
Is the size in the model number the exact capacity?
No. The code is the nominal size, the round number the unit is sold as. The capacity an air conditioner or heat pump is certified at depends on the indoor coil or air handler it is matched with, and it is usually a little below the nominal figure.
For example, the DOE certification database lists the Rheem RA14AY36AJ1N at 33,200 to 34,200 BTU/h of cooling across the indoor units it is certified with. Its size code is 36: 3 tons, or 36,000 BTU/h nominal.
The size of the unit you have is also not proof of the size the house needs. To check it, use the AC tonnage calculator or the furnace size calculator.
Where is the model number on the unit?
The model number is on the rating plate, next to the serial number.
A split system has two tags: one on the back of the outdoor unit and one on the inside of the front cover of the indoor unit.
A packaged unit has a single tag on an outside corner. An oil furnace has its rating plate on the left interior wall, just above the burner.
Model numbers this page does not read
- Rheem and Ruud outdoor units from before the Endeavor Line, such as RA1336AJ1NA or 13AJA36A01: their layout was not checked against a Rheem document.
- Packaged units (RHPX, RDFX and similar) and ductless units: they use other layouts.
When a model number does not match a layout, the decoder says so. It does not guess.
How old is the unit?
The serial number on the same plate holds the build date: Rheem serial number decoder, Ruud serial number decoder.
Questions and answers
How do I tell the tonnage of a Rheem unit from the model number?
On current models read characters 7 and 8 and divide by 12. In RA14AY36AJ1NA they are 36: 36,000 BTU/h, 3 tons. Rheem’s own model list calls the 18 a 1 1/2 ton unit and the 60 a 5 ton unit.
Is a Ruud model number read the same way?
Yes. Ruud is Rheem’s sister brand. The first letter is U in place of R and every other position is the same.
Is the furnace code the exact input?
Not always. On the Rheem R96T the code 060 is rated at 56,000 BTU/h and 040 at 42,000. On the Ruud U97MV the code is exact: 060 is 60,000 BTU/h. The rating plate gives the exact figure.
Sources
- Rheem RA14AY specification sheet: model number identification (manufacturer): https://files.myrheem.com/webpartners/ProductDocuments/5CEE16D8-4CCF-4E8D-B581-4E45F9F6714E.pdf
- Rheem RP14AY heat pump specification sheet: model number identification (manufacturer): https://files.myrheem.com/webpartners/ProductDocuments/D63B51E8-5695-4562-93C3-CDE753A40C2A.pdf
- Ruud UA18AZ specification sheet: model number identification (manufacturer): https://files.myrheem.com/webpartners/ProductDocuments/DFEEFA94-7A4F-4236-A7FB-80D112AAA577.pdf
- Rheem R96T specification sheet: model number identification (manufacturer): https://files.myrheem.com/webpartners/ProductDocuments/DE35D993-3F23-44A9-A8FB-8B6DC97E2FCF.pdf
- US Department of Energy compliance certification database: furnaces (certified input capacity for each model number) (government data): https://www.regulations.doe.gov/certification-data/CCMS-4-Furnaces.html
- Ruud U97MV specification sheet: model number identification (manufacturer): https://files.myrheem.com/webpartners/ProductDocuments/58F2BD86-5045-44DE-AD9C-7784FE53BCEF.pdf
Layouts last checked against these sources on October 5, 2026. Found a model number that reads wrong? Send a correction. How layouts are verified: method and sources.