Abstract: A fluid circulating apparatus includes a housing which forms a part of an aggregate, for instance a heat exchanger. The housing has an inlet portion for admission of fluid into a first compartment and an outlet port which communicates with a pressure chamber of the housing. One wall of the housing has at least one aperture through which fluid can flow from the first compartment into the heat exchanger proper, and at least one second aperture through which fluid flows from the heat exchanger proper into a second compartment. A pump in the pressure chamber draws fluid from the second compartment through an opening in a funnel-shaped member extending transversely through the housing and discharges pressurized fluid into the pressure chamber. An inclined wall extending between the funnel-shaped member and an opposite housing wall separates the first from the second compartment.