Patent ID: 8308853

Claim:
An electrostatic precipitator having a body and a grid of electrode elements within said body, a plurality of electro-conducting support arms connected to and supporting the grid, each of said support arms extending through a port in a wall of the electrostatic precipitator surrounding said grid of electrode elements to an external insulator compartment and terminating in an insulator which insulates the support arm from the body of the electrostatic precipitator, and a damper located in the insulator compartment and effective to selectively seal off the interior of the insulator compartment from gases flowing through the electrostatic precipitator, wherein said damper comprises a wall spanning the insulator compartment and defining respective openings through which each of said support arms extend and at least one closure element selectively moveable between a first position in which said opening is at least partially unobstructed and a second position in which the opening is completely obstructed.