The health directorate advises people to avoid working in sunlight for a long period, but rest is a luxury the poor cannot afford
Friday afternoon's incident left two others injured.
Gulshan police OC Rafiqul Islam said the accident took place on the roof of multi-storey Six Seasons Hotel.
"The AC explosion killed one on the spot," he said.
The injured have been admitted to the Dhaka Medical College and Hospital.
He, however, could not immediately identify the victims.
Fire Service's control room officer Brajen Kumar Sarkar said the building did not sustain any damage.