Disclosed is apparatus and a system thereof for reclaiming heat through the transfer of heat from normally waste hot gases to a liquid medium, usually water, and redistributing the heat by way of the liquid medium to spatially distant heat exchangers. The heat exchangers employed for initial heat reclamation are of a design uniquely adapted to avoid plugging under freezing conditions.

Method of manufacturing a heat exchanger body composed of a plurality of facially-opposed corrugated rectangular sheets of a deformable material with corrugations in alternate sheets crossing the corrugations in the intervening sheets and forming a series of channels through which two streams of gaseous medium are forced crosswise in heat exchange relationship with one another. The juxtaposed edges of the sheets are displaced so that the edges on the same side of the body are alternately sealed and form openings therebetween for admission of the gaseous media into the channels. The edges of the corrugated sheets, prior to being assembled into a heat exchange body, are pressed flat, with flat edges at two of the opposite sides extending substantially in the same plane and the contiguous flat edges at the other two opposite sides being displaced relative to the plane of the first two opposite edges.

A counterflow heat exchanger is described with two sets of heat exchanger passages separated by heat exchanger plates disposed in substantial parallelism within the exchanger and supported so that the passages extend substantially vertically. The heat exchanger may be employed as an air-to-air or as an air-to-water heat exchanger and can be used to remove moisture or pollutants from hot exhaust air by condensation within the exchanger passages. When employed as an air-to-water heat exchanger, the water is sprayed onto the surfaces of the upper ends of one set of passages so that it flows down their length, while air is transmitted into the lower end of the other set of passages and caused to flow upward. The ends of the heat exchanger plates are split into two end portions which are joined to different exchanger plates on opposite sides thereof to form the two sets of passages which allow the air and water to flow in opposite directions through such passages for counterflow heat exchange by direct lateral transfer through the thickness of the exchanger plate. In making the exchanger, the exchanger plates are arranged in substantial parallelism and edges joined together with clips which tie the plates together as a unit bundle. A layer comprising a mixture of synthetic plastic resin and reinforcing material is prepared, and the unit bundle of plates is placed with a set of longitudinal edges of the plates in such layer. When the resin hardens, the layer forms a rigid slab extending along such set of edges which seals the edges to the heat exchanger housing with an air tight seal.

A modular heat exchanger includes unitary finned tubular core elements which can be assembled into a multi-module heat exchanger without any brazed, soldered or welded connections or mechanical connectors. The modules are preferably made from extruded aluminum blocks into which the heat exchanging fins are cut or cold formed and into the ends of which flow accumulating passages are bored. The modules are assembled with a high strength adhesive sealant which simultaneously secures the modules together and seals the peripheries of the bored passages at the module interfaces.

A weld-free heat exchanger assembly core includes a plurality of stacked fin-plate assemblies. A separate enclosure bar is positioned at the end of each fin-plate assembly. A plurality of apertures are pre-drilled in the enclosure bars before assembly of the core. Once the core is assembled, it is brazed to form a unitary structure. Apertures formed in the inlet and outlet manifolds are aligned with apertures formed in the enclosure bars and fasteners are inserted into the aligned apertures. The fasteners serve to draw each manifold into tight engagement with a plurality of separate enclosure bars.