CACA Cooler

An air-to-air cooler for motors and generators

CACA coolers (Closed Air Circuit Air-cooled) are a form of air-to-air heat exchanger effective in cooling a generator or motor. They are also known as TEAAC  (Totally Enclosed Air-to-Air Cooled) coolers.


What is a CACA cooler?

A CACA cooler removes the excess heat generated by large electric motors and generators. Ambient air passes through tube bores to provide cooling while the clean machine air passes over the outside of the tubes.

The closed circuit prevents dirt particles and liquids from entering the primary cooling circuit, ensuring the lifetime of the equipment is extended and optimised.

Fan cooling to fit electric motors of any size

CACA designed and manufactured by Sterling Thermal Technology

All electrical motors and generators need an airstream to cool the equipment rotor and stator. Small electric motors simply have cooling fins on the outside of the motor frame. Larger machines generate much more heat, and direct cooling of the individual components is required.

With this air-to-air heat exchanger, direct (primary) cooling is provided by passing air through passages within the machine air circuit. A fan on the machine shaft is used for air circulation in the majority of applications. A separate machine circuit cooling fan is installed when necessary to establish a consistent airflow. Machine circuit air is forced over the outside of the CACA cooling tubes while ambient air is forced through the tubes. Axial fans are the most frequently used drivers for the ambient air supply although there are other design options available.

Why use a CACA/TEAAC cooler?

Up to IP56 protection

An advantage over other air to air heat exchangers, CACA  coolers offer levels of protection against solid and liquid ingress up to IP56 can be provided for both the cooler / machine enclosure and ancillaries such as fans and instrumentation.

Equipment availability through cooler redundancy 

By utilising excess fan capacity a very high degree of availability of the cooled equipment can be ensured.

Simple but effective

CACA motor cooling is a tried and trusted means of cooling a generator or motor in a dust-laden environment or where a water supply is not available or available at a premium.

Robust and reliable

Materials can be selected to reduce corrosion and increase both the period between maintenance interventions and overall equipment life.

For other air to air cooling solutions, view our Avantair page.

icon of a quote markWe have used CACA coolers for a number of different generator installations. Sterling Thermal Technology has an understanding of our requirements which is second to none and their products have always met our expectations

Jon Southam, Global Commodity Leader, GE Power Conversion

Design considerations

Every installation is different. Some considerations when designing a CACA motor cooling system include the below.

  • Generator / Motor construction – single or double end vented.
  • Redundancy requirements for fan operation.
  • Restrictions to the available air side pressure drop.
  • Limitations on the total installed power of air circulating fans.
  • Corrosion potential of the environment.

The specific requirements of the job will determine the best features to include.

CACA (air-to-air cooler) cooler designed and manufactured by Sterling Thermal Technology for Golden Pass LNG located in Sabine Pass in Texas
CACA cooler for the Golden Pass LNG (Texas)

We offer lots of design options to suit all applications and restraints thanks to our flexible optimising heat exchanger software. We can meet your thermal and mechanical specifications for the overall equipment requirement.

Sterling Thermal Technology can address the most stringent requirements with our design capability, quality system and production facility. We can configure CACA and TEAAC coolers for installation in hazardous and aggressive environments.

You can download this rotating machine cooler CACA product datasheet as a PDF

Whether you are an original equipment manufacturer or an end-user, Sterling Thermal Technology can help with your heat exchange needs. Contact us today, or learn more about our other technologies or the markets we work in.


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