Water Cooled Chiller Heat Rejection
Uniflair-Refrion dry and adiabatic coolers are the perfect solution to compliment tradtional water cooled chillers when used for the primary cooling source for data centres.
Water cooled chillers generally have an energy efficiency ratio (EER) around 60-70% higher than traditional air cooled chillers operating at common design conditions in the UK.
By incorporating a secodary plate heat exchanger into the condenser system design, it is possible to provide supplementary free cooling when ambient temperatures prevail:
[image of water cooled chiller with dry cooler and free cooling]
Air Cooled Chiller with Supplmentary Free Cooling Dry Cooler
Dry and adiabatic coolers have long been used as an alternative to traditional free cooling chillers, offering the advantage of greater free cooling potential.
Traditional free cooling chillers require the entire cooling system to be filled with glycol due to the potential freezing of sedentary water within the free cooling coils when the chillers are off. This led to the development of ‘glycol-free’ free cooling chillers which incorporate an internal secondary free cooling circuit separated from the main circuit by a plate heat exchanger and free cooling pump. The latter system is based around the concept of using a traditional air cooled chiller with a separate dry/adiabatic cooler to provide free cooling when ambient temperatures are lower enough to provide water at temperatures at approximately 2-3 0 C below the design chilled water temperature.
Hybrid Data Centre Cooling Solution
Modern data centres generally operate with elevated temperatures within the cold aisle. According to ASHRAE guidelines, the temperature within the cold aisle should be kept with a temperaure range of 19 to 27 0C.
In order to maminise data centre PUE values, this has led to the development of ‘Hybrid’ cooling systems whereby an adiabatic cooler is the primary cooling source which is supplemented by ‘top-up’ mechanical cooling if required.
Uniflairs ‘Hybrid DC Cooling Solution’ provides such an arrangement;