UG40 Energy Saving & Twin Cool units Functioning and Adjustment 1 Energy Saving Units Managing of free-cooling on Energy Saving units Energy saving feature is done in the following way: the unit is water cooled; the water can be cooled by a dry cooler or can be derived from a open or closet loop circuit. 2 Energy Saving Units La regolazione dei radiatori esterni può avvenire: •direttamente inviando un segnale al regolatore di velocità (è il caso di un DRY-COOLER non UNIFLAIR); •indirettamente inviando solo la commutazione del set-point al controllo indipendente della RAL (è il caso del DRY-COOLER UNIFLAIR). La regolazione diretta può essere a sua volta: •modulante, secondo la rampa sotto disegnata; •ON/OFF (per regolazione a due velocità). La regolazione, sia “diretta” che mediante “commutazione del set-point”, può essere di due tipi: •regolazione invernale, che interviene quando la differenza tra la temperatura ambiente e la temperatura esterna supera i 9°C; •regolazione estiva, che interviene quando tale differenza scende al di sotto dei 7°C. 3 Energy Saving Units The microprocessor monitors both the ambient temperature and the ΔT between the water temperature and the room temperature; its goal is to regulate the room temperature according to the room temperature set-point and to maximize the energy saving effect. Whenever the difference between the room temperature and the external temperature (ambient temperature) is greater than 8.0±0.5°C, the microprocessor requires the maximum cooling effect of the external radiators (this means that the CCU microprocessor changes the dry-cooler’s set-point from “Summer Temp.” to “Temp. E.S.”). Whenever the difference between the room temperature and the external temperature (ambient temperature) is lesser than 7.0±0.5°C, the microprocessor regulates the external radiators fans to optimize their operation in DX stage (the dry-cooler works with the “Summer Temp.” set-point). 4 Energy Saving Units The microprocessor also measures the inlet water temperature on the condenser side by an NTC sensor; when the difference between the room temperature and the inlet water temperature is greater than 6.5°C), it opens the 3-way valve in order to feed the free-cooling coil (i.e. the ES mode has started). Hence, according to the above mentioned points, the water temperature is controlled according to two different temperature levels (with consequences on the regulation of the dry-cooler’s fans) depending on the difference in temperature between the room temperature and the external temperature. 5 Energy Saving Units 6 Energy Saving Units 7 Energy Saving Units 8 Energy Saving Units 9 Energy Saving Units Uscita 7 10 Energy Saving Units 11 Energy Saving Units 12 Energy Saving Units 13 Energy Saving Units 14 Control Theory 15 16