Booster unit with vertical axis multi-impeller pump KVC, designed for pressurization tasks, rainwater reuse and use in irrigation systems in agriculture, residential building service and commercial building service. Air supply connection is included. It includes an expansion tank and a bipolar pressure switch for the single-phase version or a motor protection switchboard for the three-phase version. Single-phase version with power plug. The units are supplied assembled, set up and tested directly in the factory and complete with installation instructions, maintenance and test reports.