Airwell AWSI-DCV072-N11 Manuel D'installation page 14

Installation Procedures
The length difference between pipes should be limited
to be less than 2:1;
Make the piping as short as possible;
Keep the min. elbow quantity;
Wind the heat insulating material around the flange
between the main unit and the exhaust pipe for heat
insulation and sealing. Install the piping before fitting
up the ceiling.
6. Account of simple rectangle duct
Assume the friction resistance per unitis 1Pa/m, when the size of one side of air pipe is 25omm,
like below figure:
B 300m 3
/h
3
A 300m
/h
Account of resistance in duct:
straight pipe
bended section
air outlet section
static pressure box
inlet grille (with filter)
3
A 1200m
/h unit
A 1200m
static pressure box
with filter
(purchased additionally)
account as 1Pa per meter,
1Pa/m
each bend regarded as 3-4m
of straight pipe
account as 25Pa
50Pa per static pressure box
40Pa for each one
3
/h
simple duct selection Note:1Pa/m
m
11
incorrect incorrect
flux
3
1200m /h
A
3
(20m /min)
3
300m /h
B
3
(5m /min)
shape
flux
item
3 3
/h(m /min)
100 250
250
200
250
300
250
400
500 250
600(10)
250
250
800
250
1,000
250
1,200(20)
250
1,400
250
1,600
250
1,800(30)
250
2000
2400 250
3,000(50)
250
3,500
250
4,000 250
4,500 250
5,000 250
250
5,500
250
6,000(100)
correct
gas pipe
(mmxmm)
250x310
250x120
square pipe
size
(mmxmm)
x 60
x 90
x 120
x 140
x 170
x 190
x 230
x 270
x 310
x 350
x 390
x 430
x 470
x 560
x 650
x 740
x 830
x 920
x 1000
x 1090
x 1180