Negative Pressure-based Free Cooling Unit


Reduce Operating Costs, Save Energy, & Increase Lifespan of Equipment

Free Cooling Unit is an Energy Efficiency Cooling System for Base Transmission System Cabins and Utility Control and Monitoring Sites

Energy Efficient Cooling System

Proven effectiveness for these industries

Equipment Shelters
Data Centres
Transportation of Food
Reduce Heavy Dependency on Air Conditioner or HVAC

Telecom and utility providers are faced with the problem of hot air accumulation in BTS and control system cabins, where a constant flow of electricity and closed compartments result in increased temperature, risk of shutdowns, and a dramatic decrease in equipment lifespan.

Out with the Old, in with the New

The conventional solution is the installation of air conditioning units within the cabin, which relies on high electricity usage to effectively cool the interior air. While many industries are overhauling their air conditioning systems with more energy-efficient inverter technology, energy consumption in cooling systems is nonetheless one of the biggest contributors to high OPEX. 

Alternative Cooling Solution

With advances in Free Cooling Unit and smart technology, the operation of simply removing hot air and replacing it with significantly cooler outdoor air is more efficient than ever. Free Cooling Units can be installed independently or integrated directly into a hybrid FCU & Air Conditioning System for optimized cooling in warmer climates.

FCU Complement with HVAC

The free cooling system utilizes smart technology to provide consistent cooling and temperature control via natural air cooling and improved air flow, thus preventing the damage and shutdowns of equipment. The main purpose of the FCU is to complement or entirely replace costly air conditioner cooling systems in telecom and utility industries with the ability to reduce OPEX, save energy, increase lifespan of air conditioning systems, and increase lifespan of HVAC systems.

Negative Pressure-Based Free Cooling VS Positive Pressure-Based Free Cooling

3E Works is a leading supplier of negative pressure-based free cooling units designed for reduced energy costs and optimised temperature control in telecom BTS and utility industry monitoring and control systems or plants. 

With positive air pressure, energy is focused on pumping outdoor air into the system; on the other hand, with negative air pressure, a vacuum is created indoors by pumping the air outwards.

Negative pressure-based free cooling systems are an energy-efficient alternative to positive pressure-based free cooling; the difference being the force of the airflow.

  • Fast, Simple, and Cost-Effective Installation

  • Microprocessor-Based Controller for Accurate Temperature Control

  • Indoor and Outdoor Temperature Monitoring System

  • Intelligent Interface Software for Integrated Hybrid Functionality with Air Conditioning Units

  • Emergency Cooling

  • Can Control Up to 2 Air Conditioning Units within an Integrated Hybrid System

  • Smart and Auto Mode Functions

  • Save Electricity and Operating Costs 24/7, 365 Days a Year

  • Replace Costly Air Conditioning Units

  • Increase the Lifespan of Air Conditioning Units in Hybrid System

  • Increase the Lifespan of HVAC Systems

  • Environmentally Friendly

  • Optimal Service Intervals

  • Fully Compatible with New and Old Telecom BTS and Utility Monitoring Cabin Systems

  • Reduce Operating Expenditure at All Sites

  • Reduce Temperature Control System Maintenance Costs at All Sites


3EW Free Cooling Unit

Learn more about our products!

Negative Pressure Based FCU

Enhances the natural convection by inducing air flow.

Aeolus – Hybrid Intelligent Air Con Controller

This Aircon controller is deployed to operate 2 numbers of Aircons with desired operating temperatures for telecom shelters.


Frequently asked questions

What is free cooling unit (FCU) or free cooling system?

A free cooling unit is a system designed to maintain a certain temperature threshold of a contained space by removing or mixing the contained air with fresh, cooler air from outside.

What is the main purpose of the free cooling unit in the telecommunication and utility industry?

The main purpose is to reduce the cost of operation by reducing total run hours of air conditioner, thus reducing the maintenance.

Do we eliminate the usage of air conditioners with a free cooling unit?

Based on our research and experience in the southeast Asia climate, we highly recommend not eliminating air conditioner but working in tandem with the free cooling unit for better results.

Does free cooling unit work together with air conditioner to reduce energy consumption?

Yes. Air conditioners can be integrated with a free cooling controller to work in tandem. At 3E Works, we call it “hybrid FCU.” It is estimated that up to 30%-50% of electric consumption is reduced by integrating air conditioner with FCUs.

How does it work in real scenarios?

For example, assume a contained space temperature should not be more than 35°C and less than 25°C. The outside ambient temperature will be around a minimum of 26°C and a maximum of 38°C. Integrating air conditioner with FCU will work effectively to manage the temperature as per the threshold given, thus reducing 100% relying on air conditioner. This is done by configuring the FCU to bring the cool ambient air to maintain the temperature up to 33°C, and when the temperature rises to 33°C, the controller will turn off the FCU and start the air conditioner to maintain the temperature not to exceed above 35°C. The controller will turn off the air conditioner when the temperature reaches 30°C and turn on the FCU.

What is negative pressure-based free cooling unit?

Negative pressure-based free cooling unit works by creating low pressure within a contained space and allows fresh air to naturally filter into a contained space.

What is positive pressure-based free cooling unit?

Positive pressure-based free cooling unit works by forcing outside air to be sucked into a contained space via a filtered vent, thus pushing the old air via a well-located vent.

What are the hotspots?

A “hotspot” is a term used to describe an independent area in a contained space that is hotter than the ambient temperature of the contained space.

How to eliminate hotspots in a free cooling unit application?
  • A well-designed airflow system
  • Negative pressure-based FCU will easily eliminate hotspots, as it works by removing inside air out of the contained space compared to positive pressure-based FCU
What is CFM?

CFM is a unit of measurement which stands for cubic feet per minute. It is used to measure airflow. For example, volume is determined by multiplying length × width × height. A room that is 50 feet long, 50 feet wide, and 20 feet tall is 50,000 cubic feet. A room measuring 50,000 cubic feet would need a 50,000 CFM system to replace all the air each minute.

How frequently does air need to be replaced in a contained space?
How much CFM is needed to change the air inside a contained space?
  • The total volume of air in cubic feet is divide by how frequently the air is replaced, and the result is the total CFM. 50,000ft3 / 4 minutes (air should be replaced) = 12,500 CFM system
  • It is recommended to use more than one fan for large spaces and to use many smaller units rather than a single large unit to handle the total CFM.

Partnering with world-class manufacturers to provide the highest-quality products and systems integration services

3E Works partners with world-class FCU manufacturers to provide our clients with the highest-quality products and systems integration services. Learn more about our current FCU product here, or contact us for more information on cost savings and how an FCU can benefit your organisation today.