Patent ID: 7946339

Claim:
A heat exchanger comprising: a plurality of stacked heat exchanger modules each including a first fluid conduit having a first primary heat transfer surface, a second fluid conduit having a second primary heat transfer surface, the first primary heat transfer surface being thermally coupled to the second primary heat transfer surface; and a third fluid conduit having a third primary heat transfer surface, the third primary heat transfer surface being thermally coupled to both of said first and second primary heat transfer surfaces, so that heat can be transferred between any one of the fluid conduits and each of the other fluid conduits; wherein the first and second fluid conduits are tubular members disposed in juxtaposition, and wherein the third fluid conduit is located generally laterally adjacent to and thermally coupled to both the first and second fluid conduits; wherein the first and second fluid conduits are formed by a pair of spaced-apart plates and an intermediate plate located between the spaced-apart plates, the intermediate plate being formed with undulations defining, with the spaced-apart plates, said first and second fluid conduits, one of the spaced-apart plates defining inlet and outlet openings in communication with each of said first and second fluid conduits; and wherein said intermediate plate is a first intermediate plate, and further comprising a second undulate intermediate plate located back-to-back with the first intermediate plate.