Mitsubishi Electric Lossnay series Technical Manual page 15

•
CHAPTER 1 Ventilation for Healthy Living
Comparing Centralized Ventilation and Independent Zoned Ventilation Methods
Fan Power
Installation Area
Zoning
Design
Control
Comfort
Maintenance and
Management
Trouble influence
Costs
U-6
Centralized Ventilation Method
The air transfer distance is long, thus requiring
much fan power.
• Independent equipment room is required.
• Duct space is required.
• Penetration of floors with vertical shaft is not
recommended in terms of fire prevention.
Generalized per system.
• Design of outer wall is not lost.
• The indoor supply air diffuser and return grille can
be selected without restrictions for an appropriate
design.
• As the usage set time and ventilation volume
control, etc., are performed in a central monitoring
room, the user's needs may not be met
appropriately.
• A large amount of ventilation is required even for
a few occupants.
• An ideal supply air diffuser and return grille
position can be selected as the supply air diffuser
and return grille can be positioned without
restrictions.
• The only noise in the room is the sound of air movement.
• Antivibration measures must be taken as the fan in
the equipment room is large.
• Centralized management is easy as it can be
performed in the equipment room.
• The equipment can be inspected at any time.
• The entire system is affected.
• Immediate inspection can be performed in the
equipment room.
Because there are many common-use areas, if the
building is a tenant building, an accurate
assessment of operating cost is difficult.
Independent Zoned Ventilation Method
As the air transfer distance is short, the fan power is
small.
• Independent equipment room is not required.
• Piping space is required only above the ceiling.
Can be used for any one area.
• The number of intakes and exhaust air outlets on
an outside wall will increase; design must be
considered.
• The design will be fixed due to installation fittings,
so the design of the intakes and exhaust air
outlets must be considered.
• The user in each zone can operate the ventilator
without restrictions.
• The ventilator can be operated even during off-
peak hours.
• Consideration must be made because of the
noise from the main unit.
• Antivibration measures are often not required as
the unit is compact and any generated vibration
can be dispersed.
• Work efficiency is poor because the equipment is
not centrally located.
• An individual unit can be inspected only when the
room it serves is vacant.
• Limited as only independent units are affected.
• Consultation with the tenant is required prior to
inspection of an individual unit.
Invoicing for each zone separately is possible, even
in a tenant building.