Engineering Manual
FOUR-WAY CEILING CASSETTE INDOOR UNITS
Installation and Best Layout Practices
Selecting the Best Location
Do’s
• Place the unit where air circulation will not be blocked.
• Place the unit where drainage can be obtained easily.
• Place the unit where noise prevention is taken into consideration.
• Ensure there is sufficient strength to bear the load of the indoor
unit.
• Ensure there is sufficient maintenance space.
• Locate the indoor unit in a location that is level, and where it can
be easily connected to the outdoor unit / branch distribution unit.
Note:
If the unit is installed near a body of water, certain components are at risk of being corroded.
Appropriate anti-corrosion methods should be taken for the unit and all components.
Ceiling
Ceiling Tile
Ceiling Tile
Floor
≥13/32
≥11-13/16 inches
H = 6 feet to 12 feet
≥39-3/8 inches
≥19-11/16
≥19-11/16
≤11-13/16 inches
inches
inches
inches
Figure 169:Indoor Unit Clearance Requirements.
Installing in a High or Dropped Ceiling
High or dropped ceilings, often found in commercial buildings and
offices, may cause a wide temperature differentiation. To counter-
measure:
• Change the indoor unit mode selection to allow for higher ceilings
(see table).
• Install an air circulator.
• Set the air discharge outlet so that heated air flows in a downward
direction.
• Use a dual door system to protect the building gate or exit.
Installing in an Area Exposed to Unconditioned Air
In some installation applications, areas (floors, walls) in some rooms may be exposed to unconditioned air (room may be above or next to an
unheated garage or storeroom). To countermeasure:
• Verify that carpet is or will be installed (carpet may increase the temperature by three (3) degrees).
• Add insulation between the floor joists.
• Install radiant heat or another type of heating system to the floor.
Ceiling Height Mode Selection
≤7-1/2 feet Low Ceiling
7-1/2 feet to 8-7/8 feet Standard
8-7/8 feet to 10-3/16 feet High Ceiling
10-3/16 feet to 11-13/16 feet Very High Ceiling
Table 75:Indoor Unit High Ceiling Mode Selection Options.
Installing in an Area with High Humidity Levels
If the environment is prone to humidity levels of 80% or more (near the ocean, lakes,
etc.) or where steam could collect in the plenum:
• Install additional insulation to the indoor unit (glass wool insulation >13/32 inches
thick).
• Install additional insulation to the refrigerant piping (insulation >13/16 inches thick).
• Seal all gaps between the indoor unit and the ceiling tiles (make the area air tight) so
that humidity does not transfer from the plenum to the conditioned space. Also, add a
ceiling grille for ventilation.
Ventilation Grille
Figure 170:Installing in a Highly Humid Location.
Don’ts
• Do not install the unit near a heat or steam source, or where
considerable amounts of oil, iron powder, or flour are used.
• Do not install the unit where sulfuric acid and flammable or cor-
rosive gases are generated, vented into, or stored.
• Do not install the unit near high-frequency generators.
• Do not install the unit near a doorway.
The unit may be damaged, may malfunction, and/or will not
operate as designed if installed in any of the conditions
listed.
Due to our policy of continuous product innovation, some specications may change without notication.
©LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG” is a registered trademark of LG Corp.
128 | CEILING-CASSETTE
Multi F and Multi F MAX Indoor Unit Engineering Manual
MULTI
F
MAX
MULTI
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