Daikin VAM-FA8VE, Technical Data Manual

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2
11
• HRV
•
VKM-GA(M)V1
• HRV
•
Heat Reclaim Ventilation
267
<Calculate from the equivalent straight pipe length (le) and air flow (Q)>
Example)
Equivalent straight pipe length : 19 m, Air flow : 120 [m
3
/h]
To find a ventilating fan that can satisfy these requirements, find the intersection of the pipe resistance
curve for le : 19 [m] and the static pressure / air flow characteristics curve, and then draw a vertical line
through the intersection A until it each the abscissa. The intersection B of the vertical line and abscissa
shows the required air flow capacity of the fan. In this case, the fan rating capacity should be greater than
120 m
3
/h.
Static pressure - air flow characteristics curve
11.4 Notes for Ducted Systems
•
To connect the ventilation duct to a common (multipurpose)
duct, use a 2 m-long steel leading duct or smoke reverse flow
prevention damper per the regulations for the Building
Standard Act. In the latter case, an inspection port should be
installed on the ceiling so that the damper can be accessed
through the port.
•
If an intermediate fan is installed midway in the
duct, an inspection port should be installed on the
ceiling so that the fan can be accessed through
the port.
•
The ducting examples shown in figures
should be avoided. These invite larger
noise and smaller air flow, and adversely
affect the motor.
•
To convert a local resistance to the
equivalent straight pipe length, use the Table
A shown in the previous page.
•
For this example, the equivalent length can
be calculated as follows.
Piping part
Equivalent straight pipe length
(pipe diameter 100)
I 0.5m
II 2m
III 0.5m
IV 2m
V 5m
VI 9m
Total 19m
100
50
0
50Hz
60Hz
15m
10m
5m
25 20
50 100
Air flow (m
3
/h)
(Pa)
Pipe resistance curve
150 200
19m
B
A
Smoke reverse flow
prevention damper
Exhaust duct
Ventilating
fan
Inspection port
(450 x 450 or larger)
Common
duct
Auxiliary grille
Inspection port
Deep bend
Reduced size
Unnecessarily many bends
Inclined connection
Ventilating fan
Duct