LISKEY-AIRE Lexan 500 Floor Grilles

Liskey-Aire's floor grilles are one-piece molded G.E. Lexan Thermoplastic resin, specifically designed for the static free data center environment.

For additional features and dimensions click here.

LISKEY-AIRE MICROPROCESSOR CONTROL SYSTEM

The computer room environment is a delicate balance of temperature, relative humidity, and air cleanliness. Maintaining this precise relationship requires an air conditioning system that is capable not only of high efficiency, but of monitoring and responding to the slightest changes in environmental conditions. The Liskey-Aire microprocessor based control system offers the level of accuracy required to maintain the close tolerances demanded in today's data processing facility. With a controller accuracy of + 1/16F, and + 1/16% Relative Humidity, the Liskey-Aire System is unsurpassed in precision environmental management.

The standard microprocessor functions include:

• Digital Display of Return Air Temperature and Relative Humidity
• Programmable Environmental Control Points and Throttling Ranges
• Visual Monitoring of All Operating Modes
• Calibration of Temperature and Humidity Sensors
• Monitoring of System Protective Switches
• "Password" Access for High Security Installations
• Automatic Restart After Power Failure
• Memory and Display of Alarm Sequences
• Battery Back-Up System
• Low Voltage Protection
• Remote Alarm Contacts
  

INDIVIDUAL SYSTEMS AIR COOLED SPLIT SYSTEMS DAS/UAS

The DAS/UAS Series air cooled systems are characterized by high EER's, low installation costs, and positive head pressure control. Unlike variable speed condenser fans which sense the highest head pressure of either operating compressor, Liskey-Aire provides a positive head pressure control valve for both compressors to assure minimum head pressures are maintained during outdoor ambients as low as -30F. Large capacity receivers are factory-mounted inside the indoor section, require no heaters and assure that properly sub-cooled liquid refrigerent is fed to the expansion valves. Check valves, relief valves and rotalock connections are also supplied.

A direct drive, low profile, vertical discharge condenser is supplied with each DAS/UAS system. Individual refrigeration circuits are provided in the copper tube, aluminum fin coil which is encased in a corrosion resistant cabinet. Fan guards are provided along with a control panel and fan contactors.

DA-10 Air-Cooled Unit (shown with infrared humidifer)	UA-5 Air-Cooled Unit (shown with immersion humidifier)

AIR COOLED SELF CONTAINED SYSTEMS DASC/UASC

The DASC/UASC series contain all of the features outlined in the split system with the exception of a centrifugal fan type condenser which becomes part of the indoor unit to form a self-contained, unitized package. Condenser air is ducted to and from an outside wall; perfectly suited for high rise installations where long pipe runs are costly and impractical.
	DASC-5 Self-Contained System (rear view)

WATER COOLED SYSTEMS DW/UW

Used where a water service is readily available (i.e. cooling tower or city water) the DW/UW series of water cooled units have the highest EER of direct expansion systems. Their low installation and maintenance costs combined with full capacity regardless of ambient temperatures, have made these units proven performers. Condensers are the highly efficient, coaxial, tube-in-tube type, configured for counterflow applications and low maintenance. Factory fitted two-way head pressure regulating valves maintain minimum head pressures under varying entering water temperatures and pressures.

DW-10 Water Cooled Unit (shown with infrared humidifer)

GLYCOL COOLED SYSTEMS DGS/UGS

The DGS/UGS closed loop glycol systems are perfectly suited for applications where long pipe runs make air cooled split systems impractical. The factory-matched indoor/outdoor sections are completely factory-sealed and tested; no field evacuation and charging is required, and installation costs are minimized.
The indoor section is equipped with the same high-efficiency coaxial condensers found in Liskey-Aire water cooled systems, and two-way water regulating valves maintain constant head pressure for various entering glycol temperatures and pressures.

A perfectly matched glycol fluid cooler is supplied featuring direct drive propeller type fans in a light aluminum casing. The copper tube, aluminum fin coil is sized for proper heat of rejection at low pressure drop. A factory wired and tested control panel reduces installation time.

A glycol circulating pump with a weather-shield enclosure is also provided with the glycol system. The pump is a close coupled centrifugal type with heavy duty seals.

DG-15 Glycol Cooled Unit (shown with immersion humidifier)

DUAL COOL SYSTEMS DKS/UKS

As it's name implies, the system is actually two independent cooling systems integrated into one unit to achieve optimum efficiency. The direct result is a signficantly lower operating cost in a system which retains all of the advantages of a conventional closed loop glycol system. An auxiliary water coil has been added inside the air handler to provide "free cooling" when outdoor ambients reduce glycol loop temperatures. Drawing on the precise control capability of the microprocessor, the Dual Cool system drastically reduces operating cost for the air conditioning equipment.

DK-20 Dual Cool Unit (shown with infrared humidifier)

As soon as the glycol temperature drops below the return air temperature, a fully proportional three-way modulating valve diverts the glycol to the auxiliary water coil to pre-cool the process air Compressors are sequentially staged to meet load demands.

When the glycol temperature reaches 50OF the auxiliary coil delivers full sensible cooling capacity and compressor operation is no longer required.

Throughout the cooling mode the proportional control valve will properly modulate the flow of chilled glycol through the coil in response to return air temperatures.
In the control process, the microprocessor continuously compares return air temperature to entering glycol temperature to select the most energy efficient control mode.

The Liskey-Air Dual Cool is the fully integrated approach to closed loop energy efficiency. The economizer water coils are sized to the full face area of the evaporator coils to deliver superior cooling economy. Unlike competitive systems that suspend small I slab coils over an A-Frame evaporator, the Dual Cool system is specifically designed to take maximum advantage of low ambient cooling. The larger water coil means more "free cooling", less compressor run time, and reduced energy cost.

CHILLED WATER UNITS DC/UC

The Liskey-Aire chilled water units employ a 2/3-1/3 split coil. This design allows for complete control of cooling in addition to providing a highly effective method of dehumidification.

During normal cooling, chilled water flow is regulated by the microprocessor through the 2/3 portion of the coil, using a modulating valve. This three-way valve routes just enough water through the coil to provide necessary cooling. If additional cooling is required, the 1/3 portion is activated, via a separate valve, to control room temperature.

When the cooling mode is satisfied and dehumidification is required, the microprocessor utilizes only the 1/3 portion of the cooling coil. By activating only 1/3 Of the coil area, lower reheat requirements to maintain dry bulb conditions are realized. This extremely effective method of dehumidification results in better environmental control and lower energy costs.

DC-10 (shown with infrared humidifer)