Duct Construction - Mitsubishi Electric PRH-P8MYA Technical & Service Manual

[3]

Duct construction

• Models PRH-P8MYA/P10MYA
<A>
D
B
C
A
• Models PRH-P16MYA/P20MYA
<A>
D
B
C
A
1. In case of side flow unit (factory setting) is equipped with horizontal supply and return air openings. Duct
connection to the unit should be made with duct flanges and secured directly to the air openings with flexible duct
connectors to avoid normal noise transmission.
2. For vertical air supply, a field supply plenum should be used.
The figure above shows the recommended method for duct connection.
3. In case of top flow unit (modified when installed) is equipped with vertical supply and horizontal return air openings.
Duct connection to the unit should be made with duct flanges and securely attached to the air openings with
flexible duct connectors.
4. To prevent air leakage, all duct seams should be taped.
Ducts run in air spaces that are not air-conditioned must be insulated and provided with a vapor barrier.
Ducts exposed to the outside must be weather proofed.
For quiet operation, we recommend that the insulation on the supply duct be placed inside, lining the duct.
5. Where ducts from the outside enter a building, the duct openings in the building should be sealed with weather
stripping to prevent rain, duct, sand, etc. from entering the building.
6. Fans will not accept any external resistance to airflow and what provision is available if ductwork is to be fitted to
the external fans.
7. Correctly sized filters must be fitted and there is no provision within the unit, however the filters (field supply) may
be installed in the return air.
8. Duct earth wiring must be connected to the earth point of unit ( mark point).
.
Caution:
• Do not step on the unit.
-Step on the unit may deform top panel and result in injury.
• Outlet duct is 850 mm or more necessary to construct.
• To connect the air conditioner main body and the duct for potential equalization.
• In case of top flow unit (PRH-P16MYA/P20MYA) keep 500mm or more for canvas duct space.
<B>
F
A
B
A
E
<B>
F
H
A
I
G
B
A
E
F
A
A
G
B
F
A
A
B
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E
<A> Ex. Side flow
<B> Ex. Top flow
A Duct
B Roof curb
E
C Single duct divider
D Plenum divider
E Insulator
F
K eep duct-w ork length
850 mm or more
G Rainproof the part where the
duct flange is screwed on
(Top flow only).
H Canvas duct
(Keep 500mm or more for
canvas duct space)
I Top panel