Cooling load (heat load)

The cooling load (or heat load) is the total amount of heat an AC has to remove from a space to hold the target temperature — the sum of heat coming through the walls, roof and glass (solar gain), plus heat from people, lights and equipment, and from any outside air. It's measured in kW or tons of refrigeration, and it's the basis for correctly sizing a unit. Getting it wrong hurts both ways: an undersized unit runs flat-out and never quite cools; an oversized one short-cycles — it blasts cold, switches off, and leaves the air cool but humid and clammy — while wearing itself out faster. In Dubai the load is dominated by solar gain through glazing and roofs plus the extreme outdoor temperature, which is exactly why glazing choices (a good U-value, an insulated glass unit) and insulation make such a difference to how hard the AC must work. A proper load calculation — not a rule of thumb per square foot — is what a good installer does before recommending a size, and it's part of getting AC maintenance in Dubai and replacement right.