A gun-type burner atomize the fuel oil by forcing the oil through a nozzle and spraying it into to an gun-like airflow atomic nozzle. The liquid forms microscopic particles or globules which is well mixed and partly evaporated before ignited in the combustion chamber.
A residential gun-type burner normally requires a oil 80 - 130 psi oil pressure. Commercial and industrial burners requires 100 - 300 psi.
The gun-type is very flexible and can be used within a large range of applications, from relative small residential heaters to larger industrial heating applications