Many industrial processes require the use of compressed air. When you compress air, an inevitable by-product is heat. This heat must be dissipated to prevent damage to sensitive process components.

Air compressor Intercoolers and aftercoolers can be used to mitigate the thermal effects of air compression and so, this page will provide you with all the relevant information about them and their differences.

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Intercooler vs Aftercooler

While both these type of heat exchangers are often used interchangeably, they have a few subtle differences in the way they’re designed and operate. By design, both will cause the cooling of compressed air by removing the heat generated during the compression stage of an air compressor pump.

An effect of this heat exchange is the condensation of water vapor which is suspended within the air which can be collected allowing dry air to enter the supplied processes.

The elimination of water from compressed air will protect components that may be moisture sensitive and certainly prevent damage to equipment that may have occurred due to moisture driven corrosion.

An air compressor intercooler and aftercooler both therefore assist in the process of removing moisture and drying air for downstream use.

Intercoolers

So what is an intercooler on an air compressor? An air compressor intercooler is a heat exchanger that’s function is to remove the heat generated in air by an air compressor. A good and efficient intercooler should be able to restore the temperature of compressed air to near ambient temperature.

And now, how does an intercooler work on an internal combustion engine? An intercooler is usually found in turbocharged engines to provide cooling to the air being compressed before it enters the engine circulation.

In acting as an air intake cooling unit, intercoolers permit the supply of more air into the engine as it increases the air’s density, subsequently boosting the overall efficiency and power output of the engine.

For more information on air compressor intercoolers visit our Air Compressor Intercooler Guide!

Aftercoolers

So what is an aftercooler? An aftercooler is a mechanical cooling unit that operates on the principles of an heat exchange between two mediums, water and air or air and air. Aftercooler units can be used to attain temperatures between 5-20 degrees Fahrenheit immediately after the compressed air is released from the compression unit.

And now, how does an aftercooler work? A standard aftercooler unit is composed of tubing that contains water or air (whichever medium is chosen) and fins that help the unit achieve cooling.

When operating, ambient air is pulled into the aftercooler to help remove the moisture from the compressed air. It does so by condensation, and reduces process temperatures to satisfactory levels. Aftercoolers are manufactured as either water or air-cooled variants.

In air-cooled compressed air aftercoolers, the ambient air is directed over tubes containing the hot compressed air to remove the generated heat in a heat exchange process.

In water-cooled compressed air aftercoolers, the water is channeled through tubes running alongside the compressed air pipes to achieve the cooling of the compressed air.

For more information on aftercoolers visit our Air Compressor Aftercooler Guide!

Intercooler vs Aftercooler Differences

Intercoolers and aftercoolers are used to refer to the same device and certainly function in the same manner, but they have very subtle differences in that the circumstance they are used in varies.

An intercooler is a heat exchanger attached to an air compressor (sits between the compressor pump and storage tank) that cools the air as an immediate step during the function of the compressor. In contrast, an aftercooler is a device that operates by cooling the air emerging from an air compression unit and is usually located after the storage tank but before the air tools.

As you can see, they stay very true to their names! The intercooler is integrated into the air compression process while an aftercooler comes after the compression process.

Intercoolers & Aftercoolers in Automotive Engines

In automotive terms, intercoolers and aftercoolers refer to the heat exchangers used to cool the discharge from an air compressor. In general, a diesel cooler is referred to as a charge air coolers that are often used on turbocharged and supercharged internal combustion engines.

The main function of the charge air cooler is to cool the air compressed by the turbocharger/supercharger before it enters the engine, eventually reducing it to a lower temperature and allowing more air to enter for increased fuel combustion.

When used in automobiles, both the terms refer to the charge air cooler. It’s the most generic term for aftercoolers and intercoolers and refers to the mechanical device that sits between the turbocharger/supercharger and the engine.

Many people refer to intercoolers as aftercoolers because they’re located after the supercharger or turbocharger. This is just to give you an idea of coolers in the automotive industry, all other information provided focuses on air compressors.


If you have any questions regarding intercoolers vs aftercoolers then please leave a comment below with a photo if applicable so that someone can help you!