Ton of refrigeration (TR)

A ton of refrigeration (TR) is a unit of cooling capacity — confusingly, it's about cooling *power*, not weight. One ton equals the cooling effect of melting one ton of ice over 24 hours, which works out to 12,000 BTU/hr, or roughly 3.5 kW of heat removal. It's how air conditioners and chillers are sized: a bedroom split might be 1–1.5 TR, a large living room 2 TR, and a building's central plant is rated in tens or hundreds of tons. Getting the tonnage right matters more than people think. Undersized and the unit runs flat-out and never quite cools; oversized and it cools the air fast but short-cycles — switching off before it has dehumidified — leaving the room cold but clammy and wearing the compressor with frequent starts. In Dubai, sizing has to account for the real heat load (glazing, sun, occupancy), not just floor area, which is why a proper load calculation beats a rule of thumb. Industry bodies such as AHRI certify the capacity ratings manufacturers publish. If a room never cools or the unit cycles oddly, mismatched tonnage is a common cause worth checking during AC repair in Dubai — it relates directly to the unit's cooling capacity and its BTU rating.