Introduction; Product Information - Data Aire gForce Ultra Installation, Operation And Maintenance Manual

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INTRODUCTION

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Product Information

The Data Aire gForce Ultra environmental control, direct expansion, single and dual circuit Computer
Room Air Conditioner (CRAC) equipment provides a high sensible cooling, is self-contained, factory
assembled, piped, wired, and factory tested prior to shipment. These units include an enclosure/cabinet
assembly, fan section, filter section, cooling coil, controls, and interconnecting piping internal to unit.
The Data Aire CRAC unit provides cooling, reheat, humidification, dehumidification and air filtration.
The unit is provided with a Data Aire dap4™ microprocessor controller for precision control. The unit
must be operated in a conditioned space within the operating envelope ASHRAE recommends for data
centers. Maximum dew point is 59°F (15°C). Operating outside this envelope can alter the operat-
ing performance and decrease equipment reliability. Return air to the unit must be no cooler than the
ASHRAE recommendation of 68°F (20°C) DB and 40% RH or minimum WB of 54°F (12.2°C) for proper
unit operation. Operating below this can alter the operating performance and decrease equipment reli-
ability. Refer to ASHRAE's publication, "Thermal Guidelines for Data Processing Environments."
The unique feature of the gForce Ultra is the application of variable capacity compressors. The quest
for greater energy efficiency is continuous; efficiency benchmarks are always moving up. That's why
Data Aire is moving toward variable capacity compressor technology for quieter, more energy-saving
performance. Conventional compressors are designed to run at constant speed to handle a given
capacity requirement. But in data center applications, the capacity requirement varies. In these situ-
ations, a constant speed compressor uses various capacity-regulation techniques and can be less ef-
ficient than a compressor utilizing variable capacity technology. A variable capacity compressor (VCC),
on the other hand, saves energy and operates more quietly by varying speed to match the workload.
Tests with VCC compressors have shown an immediate energy savings and sound level reductions.
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