Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24About Your VIRGA III hybrid process cooler is designed to cool process cooling fluid using a combination of fans and a water spray. The VIRGA III is designed to maintain a consistent temperature at the designated set point. When the temperature of the process fluid rises above the set point the first fan will turn on and begin cooling the fluid. If the fluid temperature continues to rise the next fan will turn on. If the fans are sufficient to cool the process fluid to the set point the fans will begin to turn off one by one as the temperature drops. Only if the ambient air temperature around the VIRGA III becomes too high and the fans cannot reject enough heat will the VIRGA III spray water to cool the air around the tower and provide additional heat rejection. Installation Considerations The VIRGA III is equipped with lifting lugs along the top of the unit. Special care should be taken not to bump hit or otherwise stress the coil fins headers tubing or connections during the lifting or positioning of the unit. Installation of the VIRGA III should be performed by a NIMBUS installation team licensed electrical contractor or qualified and experienced member of your staff. All wiring must comply with the current edition of the National Electric Code and any relevant local electric codes. The VIRGA III is delivered with all of the internal wiring completed and it requires only a connection to three phase power. The VIRGA III requires a separate connection for the water spray pipes. NIMBUS recommends a solid pipe connection to a clean water source. The VIRGA III heat exchange coils include coated aluminum fins for chemical resistance to chemicals found in most city water. Water treatment or softening may be required if the water source has a high mineral content. If the VIRGA III is installed on an asphalt roof an oil-resistant barrier should be used. Process piping should be installed so as not to place strain on the headers and connections. Follow local building regulations regarding backflow prevention. Process fluid must enter the tower at the top and leave from the bottom. Welding debris and other foreign material should be flushed from the piping system before startup. Precautions must be taken to prevent the debris from entering the heat exchange coils. If the cooler can not be isolated from the piping system during the flushing process Questions Call 844-NIMBUS3. 1