Case Study: Enhancing Cooling Efficiency in a Legacy Data Center
Overview
A Fortune 50 Telecommunications provider faced challenges with their legacy data center cooling systems in Ashburn, VA. To demonstrate the efficacy of transitioning from Return Air Temperature Control to Supply Air Temperature Control, the client engaged Purkay Labs' Thermal Survey Service. The service helped quantify the benefits of this switch across the client’s six legacy data centers, ultimately leading to significant operational improvements.
The Project
In May 2017, the client sought to benchmark the effects of changing from Return Air Control to Supply Air Control to implement the change across various legacy facilities. The data center, encompassing 15,000 square feet with 384 cabinets and a 920 kW IT load, was initially using a Return Air Control system that was not meeting efficiency expectations. Purkay Labs provided five AUDIT-BUDDY™ systems to measure temperature, humidity, and dewpoint at each cabinet, integrating this data into a custom Interactive Data Hall program for comprehensive analysis.
The Results
Before View - Aisle Average Temp of 68.4°F
After View - Aisle Average Temp 73.6°F
The initial thermal survey showed a significant difference between the average inlet temperature of 68.4°F and the CRAC set points at 75°F, indicating inefficiencies in the existing Return Air Control system. The assessment revealed considerable variation across the aisles and in front of the CRAC units, suggesting that the cold air was mixing and diluting what should have been a closed loop system.
Following the switch to Supply Air Control between June and July, a second survey in August confirmed that the average inlet temperature had risen to 72°F. This adjustment led to several areas previously below ASHRAE recommended standards showing marked improvements. The Supply Air Control allowed the data center manager to exert more precise control over the environment, contributing to an increase in energy efficiency and a reduction in the Power Usage Effectiveness (PUE) by 0.03, resulting in an annual saving of $10,238.
Key Takeaways
Gaps in Coverage: Despite a comprehensive BMS system, the lack of detailed temperature data in areas without permanent sensors highlighted the need for a more granular approach to temperature management.
Actionable Data: The Interactive Data Hall program provided a detailed baseline comparison, helping to isolate at-risk sections and ensure compliance with ASHRAE standards.
Clear Results: The transition to Supply Air Control significantly reduced temperature variations across the facility, evidenced by more uniform color scales in thermal maps post-implementation.
Strategic Importance of Supply Control: This case study underscores the advantages of Supply Air Control over Return Air Control, particularly in managing and responding to temperature variations more effectively within large-scale data centers.
Summary
The switch from Return to Supply Air Temperature Control in the client’s data center facilitated by Purkay Labs' Thermal Survey Service significantly enhanced the overall cooling efficiency. The detailed before and after analysis provided by the AUDIT-BUDDY™ systems and the Interactive Data Hall program not only justified the changes made but also highlighted the potential for similar improvements in other facilities. This strategic shift allowed the data center to handle more load while achieving lower energy consumption and operational costs.
About Purkay Labs
Purkay Labs specializes in portable environmental monitoring systems that offer quick, reliable, and independent assessments of data center environments. Our products help data center operators manage airflow, reduce Scope II emissions, increase energy efficiency, and optimize cooling without the need for complex installations.
About the Thermal Survey Service
Purkay Labs' Thermal Survey Service provides a comprehensive evaluation of data center environments using advanced tools like the AUDIT-BUDDY™ system. This service captures detailed temperature, humidity, dew point, and delta-T measurements across multiple facility locations, enabling data center operators to optimize infrastructure and ensure efficient operation with minimal disruption to daily activities.