Duct Works - Mitsubishi Electric LGH-50RVS-E Installation Instructions Manual

4.2 Duct works

4.2.1 Connecting the ducts
(1) Fasten the duct securely to the duct connecting flange, and wrap
aluminium tape (field supply) around the joints so that there is no
air leakage.
(2) Suspend the ducts from the ceiling so that their weight will not
be applied to the Lossnay unit.
(3) Two outdoor side ducts and SA duct must be covered with heat-
insulating material in order to prevent condensation.
Taping
Room Side
CAUTION
• Also make sure to select a vent grill that does not easily
condense.
• When on-site commissioning is planned, a straight duct
length more than 10xD (D=duct diameter) from the source of
turbulence like bends, contractions and dampers etc, to the
measurement point is recommended for correct measurement.
In the United Kingdom, on-site measurement should
therefore be performed in accordance with BSRIA guideline
(Commissioning Air System. Application procedures for
buildings AG3/89.3(2001))
• Before attaching the ducts, check that no (debris or any other)
foreign matter (scraps of paper, vinyl, etc.) has found inside the
ducts.
• Do not touch the damper plate inside Lossnay unit when
connecting the ducts.
• If the ambient temperature around the Lossnay unit is close to
outdoor condition, it is recommended to insulate RA duct and
use additional insulation foam on the unit surface.
• Do not carry out the following types of duct construction.
(Doing so could cause a drop in the air volume and generate
abnormal noises.)
• Extremely • Multiple bends
sharp bends
• When RA duct is not connected, install a net or other measure
on the RA flange to prevent foreign objects from being sucked
in.
• Install the unit in a location out of direct sunlight.
Outdoor Side
Duct
Aluminium tape
Heat-insulating material
Lossnay
unit
Outdoor duct
Duct connecting flange
• Bends right next • Extreme reduction in
to the outlet the diameter of the
connected ducts
4.2.2 When changing the direction of the out
door side duct (EA/OA)
(1) Removal of the flange cover
Unscrew the flange cover mounting screws (4 pcs), and remove
the flange cover.
Flange cover
Mounting screw
(for flange cover)
(2) Installation of the duct connecting flange
1. Install the duct connecting flange using attached mounting screws.
2. Fix the removed flange cover with the removed mounting
screws (4 pcs).
Mounting screw
(Accessory parts)
Duct connection flange
Eng-8
Ceiling suspension fixture
Ceiling suspension fixture