TOSOT DC INVERTER U-MATCH AIR
59
Figure 3-1-20
CAUTION!
①
The maximum length of the duct means the maximum length of the supply air duct plus the maximum length
of the return air duct.
②
The duct is rectangular and connected with the air inlet/outlet of the indoor unit. Among all supply air outlets,
at least one should be kept open.
Bottom Return Air Installation only for Units 18k.
(2) The default installation location of the rectangular flange is at the back and the return air cover plate
is at the bottom, as shown in Figure 3-1-21.
Figure 3-1-21
(3) If the bottom return air is desired, just change the place of the rectangular flange and the return air
cover plate.
(4) Connect one end of the return air duct to the return air outlet of the unit by rivets and the other to the
return air louver. For the sake of the convenience to freely adjust the height, a cutting of canvas duct
will be helpful, which can be reinforced and folded by 8# iron wire.
(5) More noise is likely to be produced in the bottom return air mode than the backward return air mode,
so it is suggested to install a silencer and a static pressure box to minimize the noise.
(6) The installation method can be chosen with considering the conditions of the building and
maintenance etc., as shown in Figure 3-1-22.
Figure 3-1-22
Table 3-1-4 Installation of the return air duct
