Free Cooling
Chilled water systems generally depend upon water chillers to maintain year round design water temperatures, but in the UK, the ambient temperature is below 15°C for almost 75% of the year.
By installing an air blast cooler as a free cooler into the chilled water system, massive energy savings can be realised.
Principle of operation
- When the ambient temperature falls 1ºC below the temperature of the water returning to the chiller, eg. water return temperature 15ºC, ambient 14ºC, free cooling can be activated.
- Before entering the chiller, the return water automatically diverts through the free cooler, pre-cooling it thereby reducing the load on the chiller and the energy being consumed by the compressors.
- The lower the ambient falls below the return water temperature, the greater the free cooling effect and the greater the savings.
- At just 3ºC below the return water temperature, the compressors would switch off and only the low power fans on the air blast cooler would then be consuming energy.
Free Coolers
- Free coolers of this type can be retrofitted to existing chilled water systems as well as incorporating them into new ones.
- Pay back is fast and energy savings year on year considerable.
- Installations of free cooling systems and chillers can qualify for interest free UK Government backed Energy Efficiency Loans. Click here for more information
Free Cooling Chillers
When a new chilled water system is under consideration, but space is unavailable for a stand alone free cooler, one can be incorporated within an air-cooled chiller. They tend to be less efficient but worthy of consideration.
The principle of operation is the same, in that when the right ambient conditions exist, the return water first passes through the free cooling coil before entering the chiller.
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