Ductable close control units air-conditioners for vertical installation and cooling only, with optional heating by means of heating element, optional humidifer and dehumidifier for precise temperature and humidity control. Particularly suitable for precision air conditioning in servers and IT rooms and all technological applications in general. The INVERTER compressor allows the cooling capacity modulation according to the real internal load, particularly efficient at the partial loads, optimizing the power absorbed and eliminating the stating current. Units fitted with electronic expansion valve and EC INVERTER fans, upflow or downflow.