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Which Do I Need — An Air-Cooled or Water-Cooled Chiller?

Category: Equipment and Solutions

Industrial chillers serve the vital role of cooling products, machinery and equipment in industries and applications such as food and beverage, tool and die-cutting, injection molding and machine tool operations. Chillers accomplish this task by moving heat from the equipment or product to the air outside a facility. If you’re interested in using industrial chillers at your facility, you’ll have two main types of chillers to choose from — air-cooled and water-cooled.

In this post, we’ll provide information regarding the two primary kinds of chillers to help you select the one that will work best for your business.

What Are Water-Cooled Chillers?

A water-cooled chiller system includes a cooling tower, which is a tall, open-ended cylindrical concrete structure designed to remove heat from water via evaporation. Alongside its cooling tower, a water-cooled chiller also includes key components like TES reservoirs, chillers, a condenser and make-up water pumps. After the cooling tower removes heat from the water, the cooled water reduces the temperature of the refrigerant used in the cooling process. These chillers deliver maximum efficiency because of their ability to condense — the lower a chiller condenses, the more efficiently it cools.

What Are Air-Cooled Chillers?

An air-cooled chiller system does not require a cooling tower. It includes a condenser that relies on the air in the environment to provide cooling. These chillers contain four primary parts — an expansion valve, compressor, evaporator and condenser. They’re typically used with a commercial or industrial facility’s air handler system, cooling crucial fluids by absorbing heat originating from processed water.

Difference Between Water-Cooled and Air-Cooled Chillers

Both air-cooled chillers and water-cooled chillers rely on airstream for their means of heat transfer. They also both have an expansion valve, condenser, evaporator and compressor. While these chiller types are somewhat similar, you can still find some significant differences between them that makes each appropriate for different applications.

One of the biggest differences is that air-cooled chillers utilize an ambient air current, while water-cooled chillers use a humid air stream consisting of water spray and ambient air stream. Essentially, an air-cooled chiller uses air for fluid cooling, while a water-cooled chiller uses water.

You’ll typically find water-cooled machines placed indoors and air-cooled chillers installed outdoors. Since air-cooled chillers blow heat out of them, they could make a room much hotter if the space isn’t very large. Due to the potential for excess heat, they’re more suited for outdoor applications or indoor applications where there’s lots of space to disperse the heat.

In contrast, companies can install water-cooled chillers in tighter indoor spaces with minimal ventilation. Since these chillers have a cooling tower located outside a building, they don’t have to blow heat into an indoor area. Generally, companies only install water-cooled chillers indoors.

Air-Cooled Chiller vs. Water-Cooled Chiller Efficiency

One of the biggest differences between water-cooled and air-cooled chillers is their efficiency. Typically, water-cooled chillers are more efficient than air-cooled chillers. Since an air-cooled chiller relies on the ambient air’s temperature, its efficiency can be impacted by the circulating cooling air’s temperatures. When the temperature of this air is higher, an air-cooled chiller’s efficiency will decline. Due to an air-cooled chiller’s need to have a lower coolant temperature, you’ll have to expend more energy to constantly send air through the heat exchanger.

In contrast, a water-cooled chiller’s efficiency tends to be higher since these chillers don’t rely as much on ambient environmental air temperatures to function properly. Since a water-cooled chiller uses refrigeration units or cooling towers, it’s easier for these chillers to regulate chiller fluid and keep it in the best temperature range. Given their lack of reliance on air temperatures, water-cooled chillers don’t need as much energy to perform optimally.

Factors to Consider When Choosing Between Air- and Water-Cooled Chillers

Since there are some crucial differences between an air-cooled chiller and a water-cooled chiller, each may can be more appropriate for different companies depending on their needs. For example, a chiller’s noise, operating cost and environmental stability can all play a role in whether a company selects it.

As you choose between a water-cooled and air-cooled chiller, carefully consider the following factors:

  • Installation space: Air-cooled chillers generally require less space than a water-cooled chiller. You can normally install the physical unit on a rooftop, in a parking lot or anywhere else you have open space available. A water-cooled unit often requires additional space for the cooling tower and a mechanical room within your facility.
  • Operating cost: Because a water-cooled chiller provides maximum cooling efficiency, it typically costs less to operate than its air-cooled counterpart. However, air-cooled systems generally require almost no upkeep. This lack of upkeep can at least partially offset an air-cooled chiller’s higher operating costs in the form of lower maintenance expenses.
  • Noise: If you operate a business where noise control is essential, such as a professional office, laboratory, call center or studio, then a water-cooled chiller is the better option. Since these chillers don’t utilize noisy HVAC units as air-cooled chillers do, you won’t have to worry about loud noises disrupting an otherwise quiet work environment.
  • Air recirculation: If your building is surrounded by obstructions that inhibit airflow, an air-cooled chiller may not function at full capacity. A water-cooled chiller’s operation, on the other hand, is not negatively impacted by insufficient air circulation due to its use of an exterior cooling tower.
  • Environmental stability: Water-cooled chillers consume and waste more water than air-cooled chillers, resulting in less environmental stability. However, low-pressure water-cooled chillers deliver a substantial reduction in emissions over the system’s life cycle.
  • Aesthetics: If you don’t want an unsightly cooling tower looming over your property, you may prefer an air-cooled over a water-cooled chiller system.

Turn to NMC The Cat® Rental Store for Air-Cooled and Water-Cooled Chillers

At NMC The Cat® Rental Store, we carry a wide assortment of peak-performing air-cooling and water-cooled chillers you can rent for a day, week, month or longer. Our knowledgeable rental staff can also help you choose the right equipment for your applications and budget.

Browse our rental chiller selection today. If you have any questions, please feel free to contact us.