Electronic enclosure cooling system

A cooling system for use in an enclosure housing heating-emitting apparatus, which cooling system comprises, in combination, at least one fan unit comprising a support for detachably housing in the enclosure and at least one electrically driven fan mounted on the support with its axis of rotation substantially vertical and, separately formed with respect to the fan unit, at least one cooling unit comprising a support for detachably housing in the enclosure, a plurality of substantially straight open-ended tubes arranged side by side on the support with their axes lying in a common substantially horizontal plane and transversely spaced apart to form passages therebetween, one open en of each tube being positioned near one side face of the support and the other open end of each tube being spaced inwardly from the oppositely disposed side face of the support and opening into an otherwise substantially fluid-tight compartment on the support and, housed in said compartment, at least one electrically driven fan and at least one deflector associated with said fan or fans, the arrangement being such that, when the fan unit and cooling unit are detachably housed in an enclosure, air within the enclosure heated by heat-emitting apparatus housed therein is caused to flow by the fan or fans of the fan unit through the passages between the transversely spaced horizontally disposed tubes of the cooling unit and is cooled b air initially at ambient temperature which is drawn from outside the enclosure by the fan or fans of the cooling unit through tubes of the cooling unit into said compartment and is deflected by the deflector or deflectors through other tubes of the cooling unit out of the cooling unit.