York YHKJXH012BAM--FX, Service Manual, Page: 88 / 161

Enlarging chart of profile chart A
Vibration resistance hook
A
Insulation
muffler cavity (air sending)
Sacking joint
Air volume adjuster
Air outlet
Checking meatus
Air conditioner
main unit
Ceiling
Air suction grille with air filter
Please consult the after-sales service personnel for the choosing and installation of suction inlet, suction duct, discharging
outlet and discharging duct. Calculating the design drawing and outer static pressure, and choose the discharging duct
with proper length and shape.
The calculation of duct resistance (the simple calculation is as follow table)
Good example Bad example Bad example
The length difference among every duct is limited below 2:1.
Reduce the length of duct as possible as can.
Reduce the amount of bend as possible as can.
Use heat insulation material to bind and seal the part connecting main
unit and the flare part of air discharging duct. Perform duct installation
work, before the fitment of ceiling.
Calculation method of the dimension of the simple quadrate air duct
Presuming the unit length friction impedance of the duct is
1Pa/m, when the dimension of one side of the air duct is
fixed as 250mm, as shown below:
Note:1Pa/m=0.1mmAg/m
The chosen chart of simple duct
Static pressure
box
Air conditioner
Equipped with
air filter (bought)
B
A
A
A
600m 3 /h(10m 3 /min)
Duct
2400m 3 /h(40m 3 /min) 250x560(mmxmm)
250x190(mmxmm)
Air volume
48K(High) 60K
A
B
Straight part
Bend part
Air out part
Static pressure box
Air inlet grille (with air filter) Calculate as per 1m length 1Pa, 1Pa/m
Each bend takes as a 3~4m long straight duct
Calculate as 25Pa
Calculate as 50Pa/each
Calculate as 40Pa/each
100
200
300
400
500
600(10)
800
1,000
1,200(20)
250 x 60
250 x 90
250 x 120
250 x 140
250 x 170
250 x 190
250 x 230
250 x 270
250 x 310
Shape
Item
Air volume
m
3
/h(m
3
/n)
Square duct
Dimension
(mmxmm)
1,400
1,600
250 x 350
250 x 390
1,800(30)
2000
2400
3,000(50)
3,500
4,000
4,500
5,000
5,500
6,000(100) 250 x 430
250 x 470
250 x 560
250 x 650
250 x 740
250 x 830
250 x 920
250 x 1000
250 x 1090
250 x 1180
Shape
Item
Air volume
m
3
/h(m
3
/n)
Square duct
Dimension
(mmxmm)
Air Duct
Installation Procedure
88