Variable Air Volume
VAV or Variable Air Volume systems, are used to control both the ventilation and temperature to satisfy the re-
quirements of a building. Central VAV systems are considered to be the most energy efficient method to air
condition buildings. By designing central systems instead of distributed systems, a greater efficiency can be ob-
tained.
The efficiency comes from utilizing larger fans and larger chillers which have much higher efficiencies than small
motors and distributed air-cooled chillers. Savings are also seen from the decreased maintenance requirements.
The new standard
While dampers and IGVs work to maintain a constant
pressure in the ductwork, a frequency converter solu-
tion saves much more energy and reduces the com-
plexity of the installation. Instead of creating an
artificial pressure drop or causing a decrease in fan
efficiency, the frequency converter decreases the
speed of the fan to provide the flow and pressure re-
quired by the system.
Centrifugal devices such as fans behave according to
the centrifugal laws. This means the fans decrease the
pressure and flow they produce as their speed is re-
duced. Their power consumption is thereby signifi-
cantly reduced.
The return fan is frequently controlled to maintain a
fixed difference in airflow between the supply and re-
turn. The advanced PID controller of the VLT 6000
HVAC can be used to eliminate the need for additional
controllers.
Pressure
signal
VAV boxes
Flow
Flow
Cooling coil
Heating coil
D1
D2
D3
Filter
Pressure
transmitter
Supply fan
Return fan
T
3
3
VLT
®
6000 HVAC Series
18
MG.61.B5.02 - VLT
®
is a registered Danfoss trademark
Содержание VLT 6000 HVAC Series
Страница 31: ...Ordering form VLT 6000 HVAC Series MG 61 B5 02 VLT is a registered Danfoss trademark 31 Introduction to HVAC ...
Страница 63: ...Mechanical dimensions VLT 6000 HVAC Series MG 61 B5 02 VLT is a registered Danfoss trademark 63 Installation ...
Страница 75: ...VLT 6000 HVAC Series MG 61 B5 02 VLT is a registered Danfoss trademark 75 Installation ...
Страница 204: ...VLT 6000 HVAC Series 204 MG 61 B5 02 VLT is a registered Danfoss trademark ...