Abstract: A frameless heat exchanger for transferring heat from a fluid circulating therein to a surrounding environment is arranged and interconnected to accommodate thermal expansion and contraction of its parts. The heat exchanger includes a plurality of hollow tubes each extending between a first end and a second end. The tubes are arranged into a tube core where the tubes are parallel to and aligned with each other so that the first ends align and the second ends align. The tubes are joined along their first ends by a first manifold and along their second ends by a second manifold. The plurality of tubes and the first and second manifolds are interconnected for relative movement between the plurality of tubes to accommodate thermal expansion and contraction of the plurality of tubes.