Dry coolers are typically used for condenser water or process cooling, often heat rejection is compromised by both fan design and control reducing efficiency and increasing energy consumption & reduced fan energy consumption, particularly if low noise fans have been specified.
The replacement of existing AC fans with high efficiency EC fans improves airflow through the heat exchanger, increasing heat rejection and overcoming many issues with operation at high ambient temperatures, fan energy consumption can often be reduced by 50%.
Typical control is achieved by cycling fans on and off to maintain the required leaving water temperature, this means that for example with a 4 fan cooler 2 fans could operate to achieve the required water temperature, however only 50% of the heat exchanger is being utilised.
EC fans can be efficiently speed controlled from 0 – 100 %, this allows all fans to operate simoultaenously drawing air through the entire condenser while running the fans efficiently at low speed, accurate control means that energy efficiency can be maintained at all times.
The optimum water temperature from a dry cooler will vary dependant on load and ambient temperature, for example trying to achieve a 20 deg c flow will result in all fans operating at 100% for half the year, our advanced control strategy constantly monitors these parameters and adjusts the leaving water temperature to ensure energy efficiency is maintained at all times.
Many dry coolers suffer from short circuiting, where hot air leaving the heat exchanger is drawn back into the inlet, this is often caused by low noise fans or obstructions which prevent heat rejection, the use of high efficiency EC fans will reject heat further from the dry cooler reducing this effect, improving efficiency and resilience while reducing energy costs.