Mitsubishi Electric Lossnay LGH-F1200RX5-E, Technical Manual

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U-67
CHAPTER 6
•
Examples of Lossnay Applications
4. Schools
4.1 System Design Challenges
A comfortable classroom environment was necessary to improve the students’ desires to study.
Schools near airports, railroads and highways had sealed structures to soundproof the building, and thus air conditioning and
ventilation facilities were required. Schools in polluted areas such as industrial districts also required air conditioning and
ventilation facilities. At university facilities which had a centralized design to efficiently use land and to improve the building
functions, the room environment had to also be maintained with air conditioning.
System Design
•
Total floor space : 247,600 ft
2
(23,000 m
2
)
•
Building specifications : Prep school (high school wing)
Memorial hall wing
Library wing
Main management wing
4.2 System Requirements and Challenges
(1) Mainly single duct methods, fan coil unit methods, or package methods were used for cooling/heating, but the diffusion
rate was still low, and water-based heaters were still the main heating source.
(2) The single duct method was difficult to control according to the usage, and there were problems in operation costs.
(3) Rooms were often ventilated by opening windows or using a ventilation gallery; although the methods provide ample
ventilation volume, those may introduce sound coming from the outside.
4.3 Details
(1) To achieve the goals of overall comfort, saving space and
energy, an air conditioning and ventilation system with a
ceiling-embedded-type fan coil unit and ceiling-embedded-
type Lossnay was installed.
(2) Automatic operation using a weekly program timer was used,
operating when the general classrooms and special
classrooms were used.
(3) By using a ventilation system with a total energy recovery unit,
energy was saved and soundproofing was realised.
4.4 Criteria for installing air conditioning
system in schools (Example)
(1) Zoning according to application must be possible.
(2) Response to load fluctuations must be swift.
(3) Ventilation properties must be ideal.
(4) The system must be safe and firmly installed.
(5) Future facility expansion must be easy.
(6) Installation in existing buildings must be possible.
(7) Installation and maintenance costs must be low.
4.5 System Trends
(1) It was believed that environmental needs at schools would continue to progress, and factors such as comfort level,
ventilation, temperature/humidity, sound proofing, natural lighting, and color must be considered during the design stage.
(2) Independent heating using a centralized control method was mainly applied when the air conditioner unit was installed for
heating only application. For cooling/heating, a combination of a fan coil method and package-type was the main method used.
(3) The total energy recovery unit was mainly used in consideration of the energy saved during air conditioning and the high
soundproofing properties.
Classroom Layout
(Hallway) SA RA
RA
RA
RA
RA
SA
SA
RA
SA
SA SA
OA EA OA
(Veranda)
RA
LS LS
SA SA SA
(Classroom)