Sydney city streets were recently shutdown for a total of 15 hours to accommodate a critical chiller installation which required the use of a 350 tonne crane. CCN was on hand to view the project which was undertaken by Innovative Air Solutions.
In preparation for the phase out of refrigerant R22, telecommunications provider, Commander Australia, has installed a PowerPax magnetic bearing chiller which uses a more ozone friendly refrigerant, R134a.
PowerPax was selected based on it proven track record of more than 2000 installations across Australia including Canberra Hospital (ACT), the Birswood Casino (WA) as well as Macquarie University and the Australian Museum in Sydney.
Innovative Air Solutions business development manager, Scott Dredge, said PowerPax chillers can operate continuously at low load conditions - 10 per cent of full load.
"Conventional chillers have problems running at light load for long periods of time due to oil management issues in the refrigeration system," he said.
"PowerPax chillers are oil free which drastically reduces the amount of servicing required.
"With conventional chillers their COP efficiency diminishes over time due to oil coating the tubes and increasing the thermal resistance between the refrigerant and the water in the tubes."
PowerPax utilises the Danfoss Turbocor oil free centrifugal compressor. "If one compressor is offline the other compressors continue to operate unaffected, even if the compressor needs to be removed totally from the chiller the other compressors are able to operate," Dredge said.
"Starting amps per compressor is 5 amps and like most chillers can operate with variable flow design applications."
PowerPax is a wholly owned Australian company with its own manufacturing base in Melbourne. This means all engineering and service support is available locally. Moreover, PowerPax was selected by Danfoss Turbocor to have a compressor rebuilding facility located in the Melbourne factory.
Dredge said the facility will be fully operational in mid-2015. "If a compressor ever needs to be taken off site for a major overhaul this can now be done right here in Australia," he said.
PowerPax now has manufacturing plants in Australia, the United States, Germany and China supported by sales offices all over the world. Commander Australia is owned by the M2 Group which also owns Iprimus, People Telecom, Dodo and several other telecommunications companies.
Features of a water cooled, magnetic bearing chiller
Smardt-PowerPax’s water cooled chillers are among the simplest yet most efficient chillers on the market in the mid size capacity range. This is achieved through the combination of a highly efficient flooded evaporator, shell and tube condenser, integrated controls and the revolutionary Danfoss Turbocor oil free centrifugal compressor.
The design utilises oil free, magnetic bearing centrifugal compressor technology. As the compressors does not require oil, there is a significant reduction in the rate of servicing.
There is no longer any need to regulate the location or the temperature of the oil within the system. In addition, the electronic expansion valves, coupled with an integrated controller allows it to take full advantage of cooler weather conditions through reduced condensing pressures, resulting in even greater energy savings.
Smardt-Powerpax’s highly efficient flooded evaporators operate using ozone friendly R134a. All condensers are of cleanable shell and tube type, designed for minimum condensing temperatures.