Uses the same engine as the full calculator (occupants 2, one large window assumed).
| Cooling load | — |
Common 3,000 sq ft dimensions: 50×60 ft, 40×75 ft, 30×100 ft. If you searched for one of these room sizes, this is your page — the load math depends on area, not shape.
US (whole home, central system): at the moderate-climate rate of ~22 BTU per sq ft, 3,000 sq ft works out to 66,000 BTU/hr, i.e. a 5 ton + zoning unit. Your climate zone shifts this substantially:
| US climate zone | Cooling load | Central AC size |
|---|---|---|
| Zone 1 — Hot (FL, S.TX, AZ desert) | 84,000 BTU/hr | 5 ton + zoning |
| Zone 2 — Warm (Deep South, TX) | 75,000 BTU/hr | 5 ton + zoning |
| Zone 3 — Moderate (TN, NC, MO) | 66,000 BTU/hr | 5 ton + zoning |
| Zone 4 — Mild (Mid-Atlantic, PNW) | 60,000 BTU/hr | 5 ton |
| Zone 5 — Cool (Upper Midwest, New England) | 54,000 BTU/hr | 5 ton |
India: 3,000 sq ft spans several rooms — Indian homes cool room-by-room with one split unit each. Use the whole-house calculator to plan units per room instead of one big system.
These figures assume 8 ft ceilings (9.5 ft for India), average insulation and normal sun. Your real number can swing ±30% — run the full tonnage calculator with your actual room data, including ceiling height, sun exposure and occupancy.
| Area | US central AC | India (single room) |
|---|---|---|
| 2,500 sq ft | 5 ton | multiple units |
| 2,800 sq ft | 5T + zoning | multiple units |
| 3,000 sq ft | 5T + zoning | multiple units |
| 3,200 sq ft | 5T + zoning | multiple units |
| 3,500 sq ft | 5T + zoning | multiple units |
0.75 ton 1 ton 1.5 ton 2 ton 2.5 ton 3 ton 3.5 ton 4 ton 5 ton
About 66,000 BTU/hr for a 3,000 sq ft US home in a moderate climate (22 BTU/sq ft), rising to 84,000 BTU/hr in hot Zone 1 climates like Florida or Arizona.
In a moderate US climate with average insulation, a 3,000 sq ft home carries roughly 66,000 BTU/hr of cooling load, which calls for a 5 ton + zoning system. Hot climates (Zone 1–2) push the load 15–25% higher; cool climates pull it lower.
3,000 sq ft is larger than a single Indian room — size each room separately with the whole-house calculator and fit one split unit per room.
100 sq ft 120 sq ft 150 sq ft 180 sq ft 200 sq ft 250 sq ft 300 sq ft 350 sq ft 400 sq ft 450 sq ft 500 sq ft 600 sq ft 700 sq ft 800 sq ft 900 sq ft 1,000 sq ft 1,100 sq ft 1,200 sq ft 1,300 sq ft 1,400 sq ft 1,500 sq ft 1,600 sq ft 1,800 sq ft 2,000 sq ft 2,200 sq ft 2,400 sq ft 2,500 sq ft 2,800 sq ft 3,200 sq ft 3,500 sq ft 4,000 sq ft 4,500 sq ft 5,000 sq ft
How these figures are derived: BTU per square foot, honestly · refine for your exact room with the full tonnage calculator.