FreeCool Evaporative Free Air Cooling Technology Overview

Workspace Technology’s FreeCool® evaporative free air economizer technology delivers consistent equipment inlet temperatures of 21ºC to 24ºC depending on client preferences. The dew point temperatures simply do not become an issue due to the practical working temperatures.

Typical FreeCool® Configuration with FlexAisle® Hot Aisle Return Plenum Aisle Containment

FreeCool® takes external air and passes it to the raised access floor void via a ducting arrangement. Sensors located within the data centre accurately measure the equipment “inlet” temperatures. To ensure constant inlet temperatures are maintained the FreeCool® controller generates air re-circulation from the hot aisle via a simple variable speed fan arrangement.

When external ambient temperatures are above 21°C FreeCool® engages the evaporative cooling circuit to provide air which never exceeds 22°C.

For maximum energy efficiency it is recommended that FreeCool® is deployed in combination Workspace Technology’s FlexAisle® aisle containment which eliminates the mixing of hot and cold airflows within the Data Centre. The separation of airflows will ensure that the evaporative circuit is only engaged when absolutely required.

The example shown above is based on a Hot Aisle Return Plenum configuration. Hot exhaust air is extracted via the ceiling plenum to outside space.

FreeCool® Typical Airflow Schematic

  1. Fresh air is brought into the system though primary filtration and wetted filter pads
  2. Water detection provides additional security
  3. Filters remove airborne particles
  4. Isolation damper is linked to fire system
  5. Cool air is fed into void under raised floor
  6. Temperature compliant air is fed into cold aisle
  7. Warm air from hot aisle is re-circulated to heat incoming air when ambient temperatures are below set point temperature to maintain constant inlet temperature.
  8. Hot air is extracted and exhausted to outside of building

FreeCool® Practical Installation

  1. FreeCool® evaporative free air coolers are externally fixed
  2. N+1 systems provide system redundancy levels
  3. Existing CRAC systems can be retained
  4. Air is supplied to the underside of the raised floor.
  5. Standby generators only have to support 10% of the electricity consumption of the CRAC systems. Typically
  6. FreeCool® systems can be maintained with UPS support only.
  7. UPS rooms are cooled with simple ventilation systems utilising evaporative cooling
  8. FreeCool® units are linked to all fire systems for controlled shut-downs.
  9. Typical room mounted FreeCool® unit.