Abstract: A heat exchanger has a duct with a tube assembly supported by a hanger that extends through an opening in the roof of the duct. A jack is provided to raise and lower the tube assembly during maintenance. The jack includes a base with an aperture therethrough and a pair of rollers attached to the underside of the base so that the jack can be moved across the roof. A pair of fluid operated cylinders are mounted on the base and project upward on opposite sides of the aperture. A jacking frame is attached to the other ends of both the cylinders and a rod extension passes through the base aperture for connecting the jacking frame to the hanger.

Abstract: A heat exchanger has a duct through which heated gases pass. A plurality of tube panels are within the duct and each panel includes a header from which a plurality of tubes extend. A pair of hangers support each tube panel to form space in the duct above and below the tube panel for maintenance access. Baffles restrict the flow of gases through these spaces. Each hanger has a bracket attached to the header of the tube panel with a rod pivotally coupled to the bracket and extending through an aperture in the roof of the duct. The hangers are connected to structural members on the exterior of the duct in a manner that maintains the tube panel in a fixed position during operation of the heat exchanger, while allowing movement of a panel within said duct for maintenance.