12
P01432Q-rev.1
5.6 Setting of External Pressure
Refer to Section 8.6 "Selecting Static Pressure with Electrical Wiring Connection".
Model
Voltage
Static Pressure
[Standard/High]
in.W.G. (Pa)
(H,Y)IDH072B21S
208V
0.28/0.88
(*)
(70/220)
230V
0.64/1.16
(*)
(160/290)
(H,Y)IDH096B21S
208V
0.32/0.88
(*)
(80/220)
230V
0.70/1.18
(*)
(175/295)
*: Factory Setting
Figure 5.7 Duct Connection Example
Duct
Air Filter
(Field-Supplied)
Canvas Duct
Duct
Canvas Duct
Service Access Panel
Ceiling
Air Inlet
Air Outlet
● If a lower sound level is further required, install silencer (field-supplied).
● The facility design should be “Unit External Static Pressure = Duct Pressure Loss + Suction /
Discharge Pressure Loss”.
If the duct pressure loss drops below the external static pressure, air speed will increase and
lead to the occurrence of louder noise, splashing water and activation of motor protection circuit
activated. If the unit external static pressure drops below the duct pressure loss, some problems
such as inability to change the air speed may occur. Set the airflow control damper or shift the
static pressure control switch to adjust to almost equalize the level between the external static
pressure and the duct pressure loss. (See “Setting of External Pressure” section for details.)
● This unit is designed to be installed with ducts on the inlet side and the outlet side. Ask for more
information for using the return ducts in the ceiling.
5.5 Connecting Supply Duct
(1) The supply duct should be connected with the indoor unit through canvas ducts, in order to avoid
abnormal sound vibration (Refer to Figure 5.7). The unit is equipped with a pre-drilled duct flange for the
return and supply duct connection.
(2) Duct material should be non-flammable material.
(3) Perform heat insulation work over the duct to prevent condensation.