Energy-Efficient Dry Cooler
A dry cooler, also known as a free cooler, is a cooling system that uses ‘free’ outside air to cool the process fluid in a heat exchanger. These systems are ideal for businesses seeking energy-efficient, low-maintenance alternatives to chillers, especially in climates where ambient temperatures frequently dip below process fluid requirements.
In this article, we’ll discuss:
- How a Dry Cooler (Free Cooler) Works
- Why Choose a Dry Cooler for Your Industrial Cooling Needs?
- Dry Coolers vs. Chillers: What’s the Difference?
- Can You Combine a Dry Cooler and a Chiller?
- Your Dry Cooler and Chiller Experts
How a Dry Cooler (Free Cooler) Works
Dry coolers have a straightforward and sustainable principle:
- The hot process fluid, typically water or a water-glycol mixture, is pumped through a heat exchanger, also called a “coil, ” located outdoors.
- As the process fluid flows through the coil, a fan blows ambient air across the coil. This causes the heat from the process fluid to transfer to the air. Usually, a minimum difference of 10°F (~5°C) is enough.
- The process fluid is then pumped back into the facility to cool the equipment or process it is intended to cool.
Why Choose a Dry Cooler for Your Industrial Cooling Needs?
Dry coolers have numerous operational and financial advantages for various industrial cooling needs:
- Reduced energy consumption: No compressor or refrigerant cycle required
- Lower operating costs: Fewer moving parts, minimal maintenance
- Eco-friendly cooling: Uses natural air instead of synthetic refrigerants
- Quiet operation: Ideal for noise-sensitive environments
- Reliable performance: Features year-round performance in appropriate climates
Common Dry Cooling Applications include:
Dry coolers are especially effective during cooler months or in geographic areas with consistent low temperatures. Having problems with your dry cooling system? Read our article, Solving Common Problems in Air-Cooled, Water-Cooled, and Hybrid Dry Cooling Systems.
Dry Cooler vs. Chillers: What’s the Difference?
A dry cooler and a chiller are both types of cooling systems, but they operate in different ways and are used for different applications.
A chiller is a refrigeration system that removes heat from a process fluid and transfers it to a coolant/chiller fluid, typically water or a water-glycol mixture. The refrigerant then flows through a compressor, where it is compressed, and its temperature and pressure are raised. The hot refrigerant gas is then condensed in a heat exchanger, releasing the heat it has absorbed. The now-cooled refrigerant is then expanded and passed through an evaporator, where it absorbs heat from the process fluid, completing the refrigeration cycle. Chillers, also known as water-cooled chillers, are typically used for large-scale cooling applications, such as air conditioning for commercial buildings or process cooling for industrial applications.
A dry cooler, on the other hand, uses outdoor air to cool the process fluid in a heat exchanger or air-cooled coil. As mentioned earlier, the hot process fluid is pumped through a coil located outdoors, and a fan blows ambient air across the coil, which cools the process fluid. Dry coolers can be used in all cooling applications, such as cooling for plastic injection molding, food, pharmaceutical, chemical, data centers, or any other industrial processes that require cooling.
In summary, while both dry coolers and chillers are used for cooling applications, a chiller is a refrigeration system that uses a refrigerant to remove heat from a process fluid, while a dry cooler uses ambient air to cool the process fluid.
Can You Combine a Dry Cooler and a Chiller Into One Unit?
Yes— Delta T Systems’ Dry Cooler/Chiller Combo unit does exactly this. Instead of sourcing and commissioning a dry cooler and chiller separately, the Combo unit factory-assembles both into a single, function-tested package that takes advantage of the free cooling potential of ambient air when outdoor conditions allow, and switches to mechanical cooling when they don’t.
How it works:
- A proprietary control program continuously monitors ambient conditions alongside numerous system sensors to determine the most efficient operating mode.
- When the outdoor temperature is low enough, the unit relies entirely on the dry cooler coils and variable-speed EC fan motors — the hermetically sealed, variable-speed compressor draws no power at all.
- As the outdoor temperature rises, the same control brings the compressor online to provide additional mechanical cooling and maintain the setpoint.
- This automatic, sensor-driven switching is ideal for environments with fluctuating cooling loads (such as data centers or industrial processes with intermittent cooling requirements) or seasonal temperature variation.
By combining both technologies into one cabinet with one controller, the Dry Cooler/Chiller Combo reduces installation labor and long-term maintenance compared to running a dry cooler and chiller as separate systems, while capitalizing on low ambient temperatures to cut compressor run hours and energy use year-round.
Delta T Systems, Your Dry Cooler and Chiller Experts
Delta T Systems proudly designs and manufactures a line of dry coolers built for modern energy-conscious industries. Additionally, all of our products are designed and built in the USA. Our systems support a variety of industrial applications, including:
- Plastic injection molding
- Food & Beverage production
- Laboratory & pharmaceutical manufacturing
- Industrial process cooling
- Cleanroom environments
Our commitment to sustainability, efficiency, and customer service is the reason clients continue to return to us time after time for new applications. Learn more about our Dry Cooler Systems and our Dry Cooler/Chiller Combo units to see which one best serves your needs.