The usage of unified devices in the spacecrafts and aircrafts allows reducing the cost of their production, but at the same time leads to the problem of unified device characteristics harmonization with systems of a unit under design. In on-board aircraft thermocontrol systems, which ensure given temperature conditions, two unified centrifugal pumps being combined in a single hydraulic unit are often installed instead of one pump in order to provide the force circulation of coolant over the system circuit. Hydraulic unit housing acts as a base component combining two pumps into a single unit. Additionally, inlet and outlet unions common for two pumps for connection to the thermocontrol system pipelines are located in the hydraulic unit. Such a structural solution reduces a number of sealed joints, weight and sizes of inlet and outlet channels. The article represents technical characteristics of spacecrafts' unified centrifugal pumps and considers selection criteria of pumps layout in a single hydraulic unit of the thermolcontrol system. Harmonization diagrams of hydraulic characteristics of the thermocontrol system and hydraulic unit pumps are represented. Their design features are considered.