Indian convention: first two digits = tonnage×10 + star rating digit (185 = 1.5T 5★). Paste your model number for an instant decode.
Always confirm against the data plate's rated capacity line — model ranges occasionally reuse digits for non-capacity codes, and the plate is authoritative.
| Capacity code | BTU/hr | Tons |
|---|---|---|
| 09 | 9,000 | 0.75 |
| 12 | 12,000 | 1.0 |
| 18 | 18,000 | 1.5 |
| 24 | 24,000 | 2.0 |
| 30 | 30,000 | 2.5 |
| 36 | 36,000 | 3.0 |
| 42 | 42,000 | 3.5 |
| 48 | 48,000 | 4.0 |
| 60 | 60,000 | 5.0 |
Amana American Standard Blue Star Bryant Carrier Daikin Goodman Heil Hitachi Lennox LG Lloyd O General Panasonic Payne Rheem Ruud Samsung Trane Whirlpool York
On the data plate — a metal or foil sticker on the side or back of the outdoor unit (or behind the front panel on indoor split units). Use the model number, not the serial number, which encodes the manufacture date rather than capacity.
Indian convention: first two digits = tonnage×10 + star rating digit (185 = 1.5T 5★). Divide the BTU code by 12 to get tons.
Paste the model number from the outdoor unit's data plate into the decoder above — it applies Voltas's nomenclature automatically. Example: 185V Vectra = 1.5 ton 5-star.
Voltas (a Tata enterprise) uses two schemes. Modern split systems carry a two-digit shorthand key at the very start of the string; window and industrial units use a longer numeric wattage block.
Residential splits such as 183V VERTIS or 125V VECTRA open with the sizing key: 12 ≈ 1.0 ton, 15 ≈ 1.2 tons, 18 ≈ 1.5 tons. The third digit is the BEE star rating and a trailing V marks a variable-speed inverter.
Window and package models such as 4502115-WAC lead with a wattage tier: 54 ≈ 5,400 W → 1.5 tons, 45 → 1.2 tons. The decoder reads the leading tier and maps it to the nearest nominal tonnage.
The decoder above applies this nomenclature automatically. Capacity codes are nominal — always confirm against the rated-capacity line on the unit’s data plate.
Capacity decoding on this page follows Voltas’s published model-number nomenclature. To confirm a unit’s actual rated capacity and efficiency, cross-check the authoritative references below.
Tonnage is derived from nominal cooling capacity: 1 ton = 12,000 BTU/hr ≈ 3.5 kW. Indian shorthand codes (e.g. 12, 18, 24) and metric kW classes both map to these nominal tonnages.
Model-number conventions and standards evolve, and manufacturers occasionally reuse digits for non-capacity codes — the rated-capacity line on the unit’s data plate is always authoritative. Figures here are for identification and planning, not a substitute for a professional load calculation.
Different brand? Back to the full 22-brand decoder. Sizing a replacement? Check what your space really needs with the AC tonnage calculator first — the old unit may have been mis-sized.