Figure 25: Water and Refrigerant Piping Schematic
Variable Air Volume (VAV)
Start Up
Enter the duct static pressure set point value and parameters
through the keypad:
Supply Fan Speed Menu
• SAF Spd Control
– DuctSPs Spt
Variable air volume, ranging from minimum to maximum, is
obtained by using a variable frequency drive (VFD) . The VFD
can increase the fan speed from 0 rpm to the fan’s maximum
r .p .m . to provide 100% air volume . The VFD will use a
frequency (0–60 Hz) to control the fan r .p .m .
The VFD is controlled by the MCB and may have a manual
bypass .
Fan Wheel Alignment
Figure 26: Wheel-to-Inlet Funnel Relationship—13 to 36
Plenum Fans
Table 14: Wheel-to-Inlet Funnel Relationship—13 to 36
Plenum Fan
Wheel-Funnel Parameters
Size
A
B
C
13
0 .25
0 .91
3 .50
15
0 .25
0 .91
3 .50
16
0 .25
0 .91
3 .50
18
0 .38
0 .86
3 .88
20
0 .42
1 .11
3 .88
22
0 .45
1 .11
3 .88
24
0 .51
1 .11
3 .88
27
0 .55
1 .36
4 .50
30
0 .62
1 .36
4 .50
33
0 .55
1 .50
5 .00
36
0 .63
1 .50
5 .00
RELIEF
VALVE
ISOLATION
VALVE
FILTER
DRIER
SIGHT
GLASS
ISOLATION
VALVE
EXPANSION
VALVE
SUCTION
VALVE
DISCHARGE
VALVE
COMPRESSOR NO. 1
CONDENSER
EQUALIZER
CAPILLARY
EVAPORATOR
A- A
RELIEF
VALVE
ISOLATION
VALVE
FILTER
DRIER
SIGHT
GLASS
ISOLATION
VALVE
EXPANSION
VALVE
SUCTION
VALVE
DISCHARGE
VALVE
COMPRESSOR NO. .2
CONDENSER
EQUALIZER
CAPILLARY
EVAPORATOR
A- A
RELIEF
VALVE
ISOLATION
VALVE
FILTER
DRIER
SIGHT
GLASS
ISOLATION
VALVE
EXPANSION
VALVE
SUCTION
VALVE
DISCHARGE
VALVE
COMPRESSOR NO. 3
CONDENSER
EQUALIZER
CAPILLARY
EVAPORATOR
A- A
RELIEF
VALVE
ISOLATION
VALVE
FILTER
DRIER
SIGHT
GLASS
ISOLATION
VALVE
EXPANSION
VALVE
SUCTION
VALVE
DISCHARGE
VALVE
COMPRESSOR NO. 4
CONDENSER
EQUALIZER
CAPILLARY
EVAPORATOR
A- A
MODERATING
VALVE
WATER FLOW SWITCH
BYPASS
VALVE
WATER SENSORS
LOW
HIGH
E.S.
WATER
COIL
CONDENSER
WATER
OUT
CONDENSER
WATER
IN
SUCTION
LINE
EXPANSION
VALVE
BULB
CAPILLARY
12'
SECTION A - A
30°
Cross Section Reference
C
AROUND DIAMETER
EQUALLY SPACED
B
A
FROM FUNNEL END TO
FANWHEEL OPENING END
s
ysTem
C
heCk
, T
esT
,
and
s
TarT
www .DaikinApplied .com 37
IM 1032-2 • Self-Contained Air Conditioning Systems