Air-Cooled vs Water-Cooled Oil Injected Screw Air Compressor

An air compressor is a positive displacement compressor that produces energy to power commercial tools and equipment. Oil injected screw air compressors generate heat as they function, which is why compressed air and oil need to be cooled with air or water.

The choice between an air-cooled or water-cooled is made based on the air compressor’s size, environment, and utilities.

How Does an Air-Cooled Oil Injected Screw Air Compressor Work?

An air-cooled oil injected screw compressor uses ambient air to reduce the temperature of the compressed air and oil. When the oil injected screw air compressor generates heat, the air-cooled circuit reduces the hot air/oil with a fan and cooler. An air-cooled oil injected screw air compressor is the most common air compressor cooling system, making it more accessible than water-cooled systems.

How Does a Water-Cooled Oil Injected Screw Air Compressor Work?

Water-cooled oil injected screw compressor use water from an external unit to cool the compressed air and oil during the compression process. The cooling circuit reduces the heat with a shell and tube cooler. Water-cooled units are more common in machines with higher horsepower.

Energy Costs of Air-Cooled vs Water-Cooled

Energy expenditure: Air-cooled units require more power than water-cooled ones.

Electricity cost: Water-cooled compressors cost a lot of money regarding electricity, water and water treatment expenses, so you’ll save money with air-cooled equipment.

Requirements for Air-Cooled Oil Injected Screw Air Compressors

An air-cooled oil injected screw air compressor needs enough cooling air and space to provide adequate airflow. Improper planning may result in problems with regulating your commercial facility’s temperature. If the compressor room is too hot, the business could experience equipment failure and unplanned shutdowns.

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To protect your equipment and continue workflow, install ductwork from both sides of the compressor to allow air to travel throughout your space. If your business doesn’t have enough room for additional equipment, it might be better to set up a water-cooled oil injected screw air compressor

Requirements for Water-Cooled Oil Injected Screw Air Compressors

A water-cooled oil injected screw air compressor needs high-quality cooling water to function. If you get water from a lake, ocean, well or river, you’d need a cooling tower and closed-loop system to filter the water and increase your system’s lifespan.

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Unless your building already has this equipment, you’ll need to include the cost of purchasing, installing and maintaining this new machinery along with your water-cooled compressor. If you already have a closed-loop cooling system on-site, make sure it can accommodate your water-cooled compressor before you install it.

Which System Should You Choose?

Air compressors can serve various industrial applications, but you need to choose the best type for your specific business. Here are some factors to consider when looking for the right oil injected screw air compressor:

Cost of operation and resources: With the rising cost of water regulation, it’s essential to consider how much you’ll have to pay to use and maintain your equipment. Since water-cooled oil injected screw compressor utilize much more water to reduce the air’s heat, they can be expensive. Air-cooled oil injected screw compressors don’t use as much water to power their products, and they also have a lower upfront and installation cost.

The compressor room’s layout: Before choosing an air compressor, make sure the room has enough space for it. If space is an issue, you could get a few smaller compressors instead of buying one large unit and put them in multiple areas around the factory. Keep in mind that most rotary screw compressors with less horsepower usually aren’t available in water-cooled models.

The compressor room’s ventilation: Air-cooled compressors need adequate airflow to function and regulate their temperature. If the room doesn’t have the proper ventilation, the area could get too hot and the equipment could shut down, delaying projects. You also would need to keep your air-cooled compressor away from a hot boiler room or fumes. Water-cooled compressors can better accommodate small spaces and higher temperatures.

When considering these factors, remember that one type of screw air compressor isn’t better than the other. Your choice between air-cooled vs. water-cooled compressors depends on your specific application and location. 

Discuss your options with a compressed air expert before deciding which one would be appropriate for your industry.