Air Conditioners

Types

• Window AC — single box fitted in a wall opening. Cheaper and simple to install, but noisier.
• Split AC — indoor unit plus outdoor compressor, quieter and the most common choice for rooms.
• Inverter split AC — variable-speed compressor that saves electricity, especially with long daily running.
• Cassette AC — ceiling-mounted unit blowing in four directions, for halls, shops and offices with false ceilings.
• Tower and ducted AC — floor-standing or hidden units for large rooms, showrooms and auditoriums.
• VRF systems — one outdoor unit serving many indoor units across a building.

What to check before buying

• Capacity in tonnes: roughly 1 tonne for 100 to 120 sq ft, 1.5 tonne for about 150 to 180 sq ft, depending on sun exposure and occupancy.
• BEE star rating and ISEER value; higher stars mean lower electricity bills.
• Compressor type (inverter or fixed speed), refrigerant (such as R32) and condenser coil material, with copper preferred.
• Warranty separately for the compressor and the full unit, plus availability of on-site service.
• Installation: copper piping length, stand, drain, electrical point and stabiliser need.
• AMC, GST invoice and OEM authorisation.

Common brands include Daikin, Voltas, Blue Star, LG and Carrier.

Who buys them

Offices, schools, hospitals, shops, server rooms, hotels, banks, housing societies and factories.

Frequently asked questions

What AC capacity for a 150 sq ft room?

A 1.5-tonne unit is usual for a 150 sq ft room, and 1 tonne is enough for smaller or well-shaded rooms. West-facing rooms may need more.

Is a 5-star AC worth it?

For rooms used many hours a day, yes: the lower power use usually pays back over time. For occasional use, a 3-star is enough.

Window or split?

Split is quieter and cools more evenly. Choose window only where wall openings exist and budgets are tight.