GIA giatsu ROUND R32 Manuel De L'utilisateur Et D'installation page 52

Installation of the Unit
3. When unifying multiple drain pipes,
install the pipes as Fig.20. Select
converging drain pipes whose
gauge is suitable for the operating
capacity of the unit.(take the cass-
ette type unit for example)
4. When the drain hose cannot keep a sufficient gradient, it is necessary to fit a riser pipe
(field supplied) to it.
5. If the air flow of indoor unit is high, this might cause negative pressure and result in return
suction of outdoor air. Therefore, U-type water trap shall be designed on the drainage side
of each indoor unit.(Fig.21)
6. Install one water trap for each unit.
7. Installation of water trap shall consider easy cleaning in the future.
Indoor unit
Fig.21
8. Connection of drainage branch pipe to the stand pipe or horizontal pipe of drainage main
pipe
The horizontal pipe cannot be connected to the vertical pipe at a same height. It can be
connected in a manner as shown below:
NO.1: Attach the 3-way connection of the drainage pipe joint as shown in Fig.22.
NO.2: Attach the drain elbow as shown in Fig.23.
NO.3: Attach the horizontal pipe as shown in Fig.24.
Fig.22
3-way connection of
drainage pipe joint
Fig.20
Indoor unit
Joint
Fig.23
Connection of
drain elbow
18
T-joint converging drain pipes
T-joint converging drain pipes
Indoor unit
Fig.24
Connection of
horizontal pipe
Joint