Dubai · AC guide
In the UAE, AC capacity is sold in tons. Too small and the unit runs all afternoon without cooling the room; too big and it cools fast but leaves the air clammy. Here is a practical way to size it for Dubai conditions.
StringsSG · Updated
Rule-of-thumb size table
| Room size | Suggested capacity | Typical room |
|---|---|---|
| Up to 120 sq ft (11 m²) | 0.75 - 1 ton | Small bedroom, study |
| 120 - 180 sq ft (11-17 m²) | 1 - 1.5 ton | Standard bedroom |
| 180 - 280 sq ft (17-26 m²) | 1.5 - 2 ton | Master bedroom, small living room |
| 280 - 400 sq ft (26-37 m²) | 2 - 2.5 ton | Living and dining |
| 400 sq ft + (37 m² +) | 3 ton +, or two units | Open-plan villa living area |
These are rules of thumb for Dubai's climate. A proper heat-load calculation by an HVAC engineer is the right way to size a new installation.
What pushes the size up
Sun and glass
West or south-facing floor-to-ceiling glass can add a large share to the load in the afternoon.
Top floor or villa roof
Heat soaks through the roof slab; add capacity for top-floor rooms.
Kitchens and gyms
Cooking and exercise add heat; size these rooms up.
Open doors
Rooms open to corridors or stairwells cool a much larger volume of air.
Signs your unit is the wrong size
Undersized: the unit runs without stopping on summer afternoons and the room stays above the set temperature, even right after a cleaning. Oversized: it cools quickly then switches off, switches on again a few minutes later, and the room feels damp. Before replacing anything, rule out a dirty coil or low gas - they mimic an undersized unit.
Not cooling enough? Check the coil first
A dirty coil can make a correctly sized unit perform like an undersized one.
