AIREDALE R410A - Airflow Control Strategies; Constant Pressure Control Explained; Constant Air Volume Control Explained

Constant Pressure Control
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pressure is controlled using a variable speed fan that is modulated to maintain a given set point.
Constant pressure control monitors the air pressure differential between two points. In a typical application (shown
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The two pressure points, positive and negative, are routed back to an air differential pressure sensor inside the CRAC
unit. The value from the air pressure sensor is compared to the set point and a fan speed demand is generated, to
maintain the required pressure differential.
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damaged to ensure accurated pressure control).
The contant pressure system shall be commissioned by Airedale following routing of tubing from the pressure diffuser
and the unit.
A maximum of 8m/s air velocity is allowed at the diffuser so consideration must be made when locating the diffuser.
Constant Air Volume
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When faced with a change in system resistance, the fan speed modulates to obtain the air volume set point.
Constant air volume monitors the air pressure differential between two points. These two pressure points, positive and
negative, are routed back to an air differential pressure sensor inside the unit.
SmartCool™ 16 - 60
Precision Air Conditioning
26
Introduction
SmartCool Technical Manual 7525371 V1.2.0_03_2013