Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 577

(7) Installation work for air outlet ducts
Calculate the draft and external static pressure and select the length, shape and blowout.
A Blowout duct
¡ 2-spot, 3-spot and 4-spot with φ 200 type duct are the standard specifications. Determine the number of spots based on
following table.
Notes (1) Shield the central blowout hole for 2-spot.
(2) Shield the blowout hole around the center for 3-spot.
¡ Limit the difference in length between spots at less than 2 : 1.
¡ Reduce the length of duct as much as possible.
¡ Reduce the number of bends as much as possible. (Corner R should be as larger as possible.)
¡ Use a band, etc. to connect the main unit and the blowout duct flange.
¡ Conduct the duct installation work before finishing the ceiling.
(8) Connection of suction, exhaust ducts
(a) Duct connecting position
i) Fresh air inlet
¡ Inlet can be selected from the side or rear faces depending on the working conditions.
¡ Use the rear fresh air inlet when the simultaneous intake and exhaust is conducted. ( Side inlet cannot be used.)
ii) Exhaust (Make sure to use also the suction.)
Use the side exhaust port.
Air conditioner main unit.
Heat insulation
Ceiling surface
B Special blowout A Blowout duct
(Option) (Optional or marketed item)
FDR208
2-spot
Bad example
State seeing from top of unit
Side fresh air inlet
Rear fresh air inlet
Fig. 1
FDR-H
Canvas duct
(Option)
Suction hole
(Silent panel)
Suction hole
(Canvas panel)
FDR258,308 FDR408,508
2~3-spot 3~4-spot
(1) (2)
Bad example Good example
Fig. 2
Exhaust
port
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