Uses the same engine as the full calculator (occupants 2, one large window assumed).
| Cooling load | — |
Common 100 sq ft room dimensions: 10×10 ft. The load depends on area, not shape.
US (single room): at roughly 22 BTU per sq ft, 100 sq ft carries about 2,200 BTU/hr, which the DOE room air conditioner chart matches to a 5,000 BTU window or portable unit. The smallest residential central system is 18,000 BTU — installing one here would oversize the room by 8.2× and cause short-cycling.
| US climate zone | Cooling load | Room unit |
|---|---|---|
| Zone 1 — Hot (FL, S.TX, AZ desert) | 2,800 BTU/hr | 6,000 BTU |
| Zone 2 — Warm (Deep South, TX) | 2,500 BTU/hr | 6,000 BTU |
| Zone 3 — Moderate (TN, NC, MO) | 2,200 BTU/hr | 5,000 BTU |
| Zone 4 — Mild (Mid-Atlantic, PNW) | 2,000 BTU/hr | 5,000 BTU |
| Zone 5 — Cool (Upper Midwest, New England) | 1,800 BTU/hr | 5,000 BTU |
India (single room, split AC): at hot-climate loads (~100 BTU/sq ft once ceiling and sun factors apply), a 100 sq ft room needs about 10,000 BTU/hr → a 1 ton split. Top floor under an RCC roof, or large west-facing windows? Step up half a ton or pick a high-ISEER model.
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.
0.75 ton 1 ton 1.5 ton 2 ton 2.5 ton 3 ton 3.5 ton 4 ton 5 ton
About 2,200 BTU/hr in a moderate US climate, which matches a 5,000 BTU window or portable unit.
No. The smallest residential central system is 18,000 BTU, which is 8.2× the load of a 100 sq ft room. It would short-cycle and leave the room cold and humid.
A 1 ton split — Indian room loads run near 100 BTU/sq ft once ceiling height and sun are counted.
100 sq ft 120 sq ft 150 sq ft 180 sq ft 200 sq ft 250 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 3,000 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.