Up to 140 sq ft: 1–1.5T (1.5T if top floor or sunny). 140–180 sq ft: 1.5T standard. 180–250 sq ft: 2T. Above 250 sq ft in one room: 2.5T or two units. Then adjust: +half ton for tin roofs, harsh west sun in hot-dry cities, or rooms packed with people and electronics.
A 2T 5★ inverter draws ~1.38 kW against ~1.03 kW for 1.5T — at 8 h/day and ₹7/unit, about ₹580 more per month if both run flat out. In practice an inverter 2T in a correctly-2T room modulates down and the gap shrinks; a 2T forced into a 1.5T room short-cycles and wastes the premium twice — purchase price and electricity.
Genuinely between sizes? In humid cities take the smaller with a high ISEER (better dehumidification); in hot-dry cities with roof exposure, take the larger. Or remove the guesswork: the calculator applies all the factors at once.
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In temperate cities or shaded mid-floor rooms, often yes. In hot-dry cities, on top floors, or with west glass, a 200 sq ft living room is honest 2T territory.
Yes — and that's the trap: it hits the setpoint before dehumidifying, then cycles. Faster isn't better in a room that only needs 1.5T.
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