Computer Room Air Conditioning (CRAC) devices are devices that monitor and maintain the temperature, air distribution, and humidity of a network room or data center. CRAC units are replacing air conditioning units previously used to cool data centers. According to Industrial Market Trends, server mainframes and racks can be as hot as a power toaster oven in a 7-foot tower, so temperature control is an important part of data center infrastructure.
There are many ways in which CRAC units can be deployed. One of the successful CRAC setups is the process of cooling the air and distributing it through a raised floor. Air rises through the perforations, forming cold passages. Cold air flows through the rack to absorb heat before leaving the rear of the rack. The warm outlet air forms a hot aisle behind the rack and the hot air returns to the CRAC inlet located above the floor.
They place the computer and rack on a raised floor that is two tiles apart with the air intakes facing each other. The CRAC cooling system pumps cold air through the perforated floor tiles between the racks, while the computer and rack draw in the cold air and exhaust the hot air into the opposite hot aisle. The computer room air conditioning unit on the floor draws the exhausted hot air into the hot aisle and discharges it under the floor tiles to complete the cycle. It has become common to utilize the space above the computers and racks and create another “hot aisle” in the ceiling of the room where the heat usually escapes and lingers. To keep the entire computer room cool, technicians recommend placing ducts and more CRAC units to convert the area above the racks into hot air plenums. Hot air can be drawn out of the plenum and pushed back into the system below the floor where it can be cooled and discharged back into the system.
It works in the computer room by removing hot air from the data center. Bringing in hotter return air helps the CRAC unit’s heat exchanger create cooler air and pump it to the computer room floor.