Senior Thesis e-Studio

DEPTH

Variable Refrigerant Flow System

The variable refrigerant flow system (sometimes referred to as variable refrigerant volume, VRV) is a system that was found to be a worthwhile study when evaluating several options for the Oklahoma University Children’s MOB.  VRF technology is not a cutting edge system; it has been popular in China, Japan, and parts of Europe for several decades, but until recently it was not popular among the HVAC industry within the United States.
The important factors that caused this system to take precedence for the Medical Office Building are as follows:

• system high efficiency,
• increased controllability,
• possibility of simultaneous heating and cooling,
• a comparably small footprint, and
• possible decreases energy consumption and emissions

BREADTH ONE

Acoustics Analysis of Mechnical Equipment

The changes proposed above to incorporate VRF boxes into each space should reduce the sound created by air handling units in the mechanical spaces and each of the individual occupied spaces.  This is mainly due the absence of the originally required VAV boxes, which were designed to serve individual spaces and zones.  It is reported that indoor units for VRF systems operate at sound levels as low as 27 dB and 29 dB when they are connected to supply air duct work.

BREADTH TWO

Electrical Analysis of New Equipment and Connections

With the implementation of different mechanical equipment and the exchange of others, it will be important to investigate whether the existing electrical distribution equipment is adequate for the new VRF equipment.  Electrical equipment such as conductors, circuit boards, and conduit are going to need to be sized according to their characteristic load amps, horsepower, and voltage.  Motor starters will be sized for any mechanical equipment such as pumps and fans applicable to the VRF system design.  The National Electric Code will be utilized for all of the sizing and calculations.

NOTE: While great efforts have been taken to provide accurate and complete information on the pages of CPEP, please be aware that the information contained herewith is considered a work-in-progress for this thesis project. Modifications and changes related to the original building designs and construction methodologies for this senior thesis project are solely the interpretation of Alec Canter. Changes and discrepancies in no way imply that the original design contained errors or was flawed. Differing assumptions, code references, requirements, and methodologies have been incorporated into this thesis project; therefore, investigation results may vary from the original design.