Computer Room Air Conditioning Replacement

The National Weather Service (NWS) Weather Forecast Office (WFO) located Little Rock, AR (LZK) are in need of replacement of its Computer Room Air Conditioning (CRAC) units. The existing Liebert units have deteriorated to the point that replacement is the best option. The Equipment Room uses these units for critical cooling and is vital to daily operations. During a recent Facility Conditioning Assessment the CRAC units were reported to be in need of replacement.Provide all labor and materials to replace existing CRAC units with new systems serving site Equipment, Electric, and Communications Rooms. Based upon estimated heating & cooling loads, Little Rock will require 10 ton Liebert, or equivalent systems. Equivalency will be based upon system performance, reliability, energy efficiency, footprint, and warranty. Perform cooling load calculations for LZK sites and size new equipment to meet demand in all seasons. Systems must continually maintain rooms between 65-74 degrees Fahrenheit and 45-55% Relative Humidity. All new systems must have N+1 redundancy to ensure system availability in the event of component failure. Components (N) must have at least one independent backup component (+1). New system must automatically transfer to the backup unit upon primary system failure to maintain set point. New systems must automatically switch lead system to lag each month to balance operating hours between primary and standby systems. Enable monitoring and control of new systems through integration with existing Building Automation System. Refer to as-built mechanical drawings for original installation. (Copies available upon request) Heating and cooling must be maintained in the Equipment room 24 hours x 7 days per week without interruption..