The continuous operation of data centers depends on maintaining a cool, consistent climate for the sensitive computer equipment inside. Computer room air conditioners (CRAC) provide the high-capacity cooling these facilities require. Proper maintenance keeps CRAC units running efficiently to ensure ideal temperatures for IT infrastructure.
How CRAC Units Work?
Computer room air conditioners contain components specialized for data center environments:
- Compressors – Circulate and compress refrigerant to absorb facility heat. Commercial-grade compressors are rugged and efficient.
- Evaporator coils – Refrigerant evaporates here, cooling air as it passes over the coils.
- Condenser coils – Expel the facility’s absorbed heat outside as hot air or water.
- Blowers – Powerful fans circulate cooled air into the room via vents. High airflow rates quickly lower temperatures.
- Humidifiers – Regulate moisture levels, preventing static electricity and dry air damage.
- Filtration – Multi-stage air filters block dust and contaminants from sensitive IT equipment.
Computer room units utilize a closed-loop system for self-contained cooling without mixing data center air with outside air. Units connect to facility chillers for larger-scale heat removal and distribution.
Benefits of CRAC Units
CRAC units provide specialized capabilities that standard comfort cooling cannot match:
- Precision – Maintain temperatures within narrow ranges like 68-72°F for equipment safety.
- High capacity – Remove heat loads from high-density computer equipment measured in kilowatts or megawatts.
- Airflow – Optimized airflow patterns and volumes to effectively cool server racks.
- 24/7 operation – Continuous cooling meets nonstop data center workloads.
- Redundancy – Facilities have backup units for immediate failover with no disruption.
- Monitoring – Networked units enable remote monitoring and control.
For reliable data center functionality, the extreme cooling power and environmental precision of CRAC units is mandatory.
Essential CRAC Maintenance
With constant operation under heavy loads, CRAC units require regular maintenance to ensure availability:
- Coil cleaning – Condenser and evaporator coils accumulate dust and debris and need periodic cleaning. Buildup on coils reduces cooling capacity and efficiency.
- Filter changes – Air filters safeguard computer equipment from particles but get loaded with contaminants over time. Technicians replace clogged filters proactively.
- Refrigerant top-offs – Refrigerant may slowly dissipate from seals and connections. Technicians test levels and top off the closed-loop system as needed.
- Belt inspection – Technicians check belts that drive blowers to look for wear and re-tension or replace as necessary.
- Drain inspections – Condensate drains are checked for obstructions to prevent overflow incidents.
- Sensor calibrations – Sensors drifting from calibrated setpoints are recalibrated for peak monitoring accuracy.
- Leak checks – Units are inspected for refrigerant leaks around joints and seals to prevent losses.
With rigorous preventive maintenance, CRAC units can operate reliably 24/7 for years before needing major repairs.
CRAC Unit Types
While all CRAC units provide specialized cooling, there are configuration differences:
- Downflow units – Cool air discharges downward through perforated floor tiles. Servers draw air up through cabinets for targeted cooling.
- Upflow units – Cool air releases upward to the hot aisle containment space around server racks. This approach focuses cooling on hot emission areas.
- In-row units – Compact in-row CRAC units fit between server racks for precise, localized cooling rather than room-level cooling.
- Portable units – Self-contained portable CRAC units on casters flexibly cool hotspots and provide temporary cooling during maintenance.
- Monolithic units – Large-capacity monolithic CRAC units house all components in a box. This consolidated design requires less ductwork.
Facilities select CRAC systems tailored for rack layouts, hot aisle containment, and other data center characteristics.
Keep Your Data Center Cool
The intricate computer equipment populating modern data centers requires environmental conditions that only specialized CRAC units can reliably provide 24/7. With capacity in multiple tonnage ratings and redundancy capabilities, CRAC systems form the backbone of data center cooling. Thorough preventive maintenance ensures these indispensable units continue effectively regulating temperatures, airflow, and humidity levels that keep sensitive technology operating optimally. By partnering with expert CRAC service technicians, data center operators can have confidence their critical environment will remain cool in the face of continuous heat output.