Table of Contents
Advertisement
3-22. Increasing the Fan Speed
If external static pressure is too great (due to long extension
of ducts, for example), the airflow volume may drop too low at
each air outlet. This problem may be solved by increasing the
fan speed using the following procedure:
(1) Remove 4 screws on the electrical component box and
remove the cover plate.
(2) Disconnect the fan motor sockets in the box.
(3) Take out the booster cable (sockets at both ends) clamped
in the box.
(4) Securely connect the booster cable sockets between the
disconnected fan motor sockets in step 2. (Fig. 3-67)
Electrical component box
Booster cable
Fan
motor
Fan motor socket
(At shipment)
(5) Place the cable neatly in the box and reinstall the cover
plate.
Indoor Fan Performance
18 Type
150
100
50
HT
H
M
L
0
10
15
3
Airflow (m
/minute)
36 Type
150
100
H
50
M
L
0
20
30
3
Airflow (m
/minute)
NOTE
HT : Using the booster cable
H : At shipment
Big_PAC_eng.indb 29
Big_PAC_eng.indb 29
Booster cable
(Booster cable installed)
Fig. 3-67
25 Type
15
150
15
10
10
100
HT
H
5
5
50
M
L
0
0
0
10
20
3
Airflow (m
/minute)
48 Type
15
150
HT
10
100
HT
H
5
50
M
L
0
0
20
30
3
Airflow (m
/minute)
Fig. 3-68
■ How to read the diagram
The vertical axis is the external static pressure (Pa) while
the horizontal axis represents the airflow (m
characteristic curves for "HT", "H", "M" and "L" fan speed control
are shown. The nameplate values are shown based on the
"H" airflow. For the 25 type, the airflow is 18 m
the external static pressure is 49 Pa at "H" position. If external
static pressure is too great (due to long extension of ducts,
for example), the airflow volume may drop too low at each air
outlet. This problem may be solved by increasing the fan speed
as explained above.
15
10
5
0
40
29
3
/minute). The
3
/minute, while
2009/08/26 16:33:14
2009/08/26 16:33:14
Advertisement
Table of Contents
