In-Line Blower
What is an 'In-Line' vs. 'Internal' blower?
Remote Extraction Mechanics
An internal blower sits inside the hood; an in-line blower is mounted in the attic or crawlspace. In-line systems are significantly quieter at the cooking surface because the motor noise is isolated from the kitchen via the duct run.
A remote blower mounted within the duct run (attic or joist) to significantly reduce noise levels at the cooktop.