Packaged rooftop units are being used in many applications today not only for cooling but for comfort and humidity control. Indoor space humidity levels can be increasingly difficult to control depending on the time of year, location and the ability of the equipment to provide flexible operations to meet indoor part load, sensible and latent load requirements. Carrier’s Humidi-MiZer® Adaptive Dehumidification System is designed to meet these requirements. The Humidi-MiZer® unit’s will respond based on the temperature and humidity requirements as sensed in the space. This is achieved by a thermostat with a built in humidity sensor (thermidistat) or a separate thermostat with a humidistat.

The Humidi-MiZer unit’s operational flexibility to maintain year round indoor comfort and humidity levels is due to its three operational modes and the controls that help achieve it. There is a liquid line solenoid valve and a discharge gas solenoid valve that open and close to direct refrigerant depending on the operational mode of the Humidi-MiZer unit.

The cooling mode provides sensible and latent cooling from the evaporator coil. During the cooling demand only the liquid line solenoid valve is de – energized and open(NO), the discharge gas solenoid valve is closed (NC). In the cooling mode only the system performs like any other package A/C unit.