Engineering Manual
Table Of Contents
- Convergence of Technology, Innovation, Flexibility, & Style
- Unit Nomenclature
- Outdoor Unit Overview
- Indoor Unit Overview
- Controls and Options Overview
- Art Cool Mirror Indoor Units
- General Data / Specifications
- Dimensions
- Cooling Capacity Table
- Heating Capacity Table
- Acoustic Data
- Air Velocity and Temperature Distribution
- Refrigerant Flow Diagram
- Wiring Diagram
- Factory Supplied Parts and Materials
- Installation and Best Layout Practices
- Art Cool Gallery Indoor Units
- General Data / Specifications
- Dimensions
- Cooling Capacity Table
- Heating Capacity Table
- Acoustic Data
- Air Velocity and Temperature Distribution
- Refrigerant Flow Diagram
- Wiring Diagram
- Factory Supplied Parts and Materials
- Installation and Best Layout Practices
- Standard Wall-Mounted Indoor Units
- General Data / Specifications
- Dimensions
- Cooling Capacity Table
- Heating Capacity Table
- Acoustic Data
- Air Velocity and Temperature Distribution
- Refrigerant Flow Diagram
- Wiring Diagram
- Factory Supplied Parts and Materials
- Installation and Best Layout Practices
- Duct (Low Static) Indoor Units
- General Data / Specifications
- Dimensions
- Cooling Capacity Table
- Heating Capacity Table
- External Static Pressure
- Acoustic Data
- Refrigerant Flow Diagrams
- Wiring Diagram
- Factory Supplied Parts and Materials
- Installation and Best Layout Practices
- Duct (High Static) Indoor Units
- General Data / Specifications
- Dimensions
- Cooling Capacity Table
- Heating Capacity Table
- External Static Pressure / Acoustic Data
- Refrigerant Flow Diagrams
- Wiring Diagrams
- Factory Supplied Parts and Materials / Installation
- Installation and Best Layout Practices
- Four-Way Ceiling Cassette Indoor Units
- General Data / Specifications
- Dimensions
- Dimensions
- Cooling Capacity Table
- Heating Capacity Table
- Acoustic Data
- Air Velocity and Temperature Distribution
- Refrigerant Flow Diagram
- Wiring Diagram
- Factory Supplied Parts and Materials
- Installation and Best Layout Practices
- Vertical-Horizontal Indoor Units
- General Data / Specifications
- Dimensions
- Cooling Capacity Table
- Heating Capacity Table
- External Static Pressure
- Acoustic Data
- Refrigerant Flow Diagram
- Wiring Diagram
- Factory Supplied Parts and Materials
- Installation and Best Layout Practices
- Equipment Selection Procedure
- Building Ventilation Design Guide
- Placement Considerations
- Refrigerant Piping Design
- Design Guideline Summary
- Creating a Balanced System / Manual Layout Procedure
- LG Engineered Multi F MAX Y-Branch Kit
- Refrigerant Charge
- Installation & Layout Best Practices
- Refrigerant Piping System Layout
- Piping Insulation
- Condensate Drain Piping
- Y-Branch Kit
- Wiring Connections
- Power Wiring (208-230V) and Communications Cable Details
- Indoor Unit Group Control
- Acronyms
Mechanical Specications and Features
DUCT (LOW STATIC) INDOOR UNITS
Ceiling-Concealed Duct (Low Static)
Indoor Unit
General
All LG indoor units are factory assembled, wired, piped, and pro-
vided with a control circuit board, fan, and motor. Ceiling-Concealed
Duct (Low Static) units have a sound rating no higher than 36 dB(A)
as tested per KSA0701 ISO Standard 3745, and are designed for
low-static pressure up to 0.20″WG.
Coil
Indoor unit coils are factory built and are comprised of aluminum fins
mechanically bonded to copper tubing. Each unit has two rows of
coils, which are pressure tested at the factory. Each unit is provided
with a factory installed condensate drain pan below the coil.
Refrigerant System
System is designed for use with R410A refrigerant. The refrigeration
circuit is pressure-tested at the factory and shipped with a holding
charge of helium gas. Refrigerant pipe connections are 45° flare,
and all refrigerant lines from the outdoor unit to the indoor units must
be field insulated.
Electrical
Each indoor unit is designed to operate using 208–230/60/1 power
with voltage variances of ±10%.
Casing
The case has a low profile design with a maximum height of 7.5
inches designed to mount fully concealed above a finished ceiling in
as little as 8 inches vertical space. Casing is manufactured of gal-
vanized steel plate, and provided with hanger brackets designed to
support the weight on four corners. Unit has a front horizontal supply
air discharge outlet, and one rear horizontal return air inlet; unit is
also field-convertible for a rear bottom return.
Fan Assembly and Control
The units have at least two direct-drive, Sirocco fans made of
high strength ABS HT-700 polymeric resin that are statically and
dynamically balanced. The fans are mounted on a common brush-
less digitally controlled (BLDC) motor with permanently lubricated
and sealed ball bearings. The fan / motor assembly is mounted on
vibration-attenuating rubber grommets. Fan speed is controlled using
a microprocessor-based direct digital control algorithm. The indoor
fan has Low, Med, High, and Auto settings for Cooling mode; and
has Low, Med, High, and Auto settings for Heating mode. Each of the
settings can be field-adjusted from the factory setting (RPM / ESP).
The Auto setting adjusts the fan speed based on the difference
between the controller set-point and space temperature.
Air Filter
Return air is filtered with a factory-supplied, removable, washable
filter accessible from the rear of the indoor unit.
Microprocessor Control
The unit is provided with an integrated control panel to communicate
with the outdoor unit. All unit operation parameters are stored in non-
volatile memory residing on the unit microprocessor. The micropro-
cessor controls space temperature through using the value provided
by the temperature sensor within the indoor unit. The microprocessor
control will activate indoor unit operation when the indoor room tem-
perature falls below or rises above a setpoint temperature, at which
point, a signal is sent to the outdoor unit to begin the appropriate
mode. The microprocessor will also provide self-diagnostics and auto
restart functions. A field-supplied four-wire power / communications
cable must be installed to connect the indoor unit(s) to the outdoor
unit.
Controls
The indoor unit is supplied with an LG wired controller. Communica-
tion between the indoor units and the outdoor unit is accomplished
through 18 AWG, four-core, stranded and shielded power / communi-
cation cable.
Condensate Lift/Pump
The indoor unit is provided with an externally mounted, factory
installed and wired condensate lift/pump capable of providing a mini-
mum 27.5 inch lift from the bottom surface of the unit. Drain pump
has a safety switch to shut off the indoor unit if the condensate rises
too high in the drain pan.
Figure 122: Ceiling-Concealed Duct (Low Static) Indoor Unit.
• Inverter (Variable speed fan)
• External mounted drain pump
• Control lock function
• Auto operation
• Auto restart operation
• Dehumidification function
• Two thermistor control
• External static pressure control
• Self-diagnostics function
• Group control
• Wired thermostat included
Features
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.
90 | DUCT (LOW STATIC)
Multi F and Multi F MAX Indoor Unit Engineering Manual
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