An apparatus is provided that includes a length of pipe having a passageway for communicating a liquid under pressure therethrough, and at least one nozzle in communication with the passageway. The at least one nozzle is configured to discharge a liquid, a portion of which is discharged in a stream, and a portion of which is discharged in a volume of aspirated spray. The aspirated spray effectively shields the pipe and the at least one nozzle from heat radiating within the enclosure. The apparatus further includes a displacement device for controllably displacing the length of pipe. The length of pipe and at least one nozzle are configured to be extended through an opening in the enclosure for discharging a stream of liquid for cleaning a surface within the enclosure.