The invention relates to a heat exchanger for heat exchange between fluids, comprising a housing having an inlet and an outlet for each fluid, the inlet and outlet for each fluid being connected to one another by a flow path, the flow path of a first fluid comprising multiple heat exchange modules comprising at least one longitudinal hollow tube, wherein the modules are arranged in a matrix configuration that comprises at least two columns of longitudinal tubes and at least two rows of longitudinal tubes, and wherein a module is provided with at least one connector for connecting to a co-operating connector of an adjacent module, such that the space enclosed between adjacent modules defines a flow path for a second fluid, parallel to the flow path for the first fluid.