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
Device Connection Limitations
• The minimum number of connected and operating indoor units to Multi F / Multi F MAX systems is two, taking into consideration of the
minimum combination ratio.
• The maximum number of indoor units for each Multi F / Multi F MAX heat pump systems is:
LMU18CHV = 2 LMU24CHV = 3 LMU36CHV = 4 LMU540HV = 8
REFRIGERANT PIPING DESIGN
Design Guideline Summary
One of the most critical elements of multi-zone systems is the refrigerant piping. The following pages list pipe length limits that must be
followed in the design of Multi F and Multi F MAX refrigerant pipe systems:
Table 106:Equivalent Piping Length for Elbows, Y-branches, and Branch
Distribution Units.
Max. 49.2 feet
Max. 24.6 feet
A
B
C
D
Multi F System
Example: LMU36CHV outdoor unit with four (4)
indoor units connected.
ODU: Outdoor Unit.
IDU: Indoor Unit.
A, B, C, D: Pipes from Outdoor Unit to Indoor Unit.
Outdoor Unit
Minimum Length for Each
Pipe (ft.)
Maximum Piping Length to Each Indoor Unit (ft.)
Maximum Total Piping Length for Each
System (ft.)
A B C D
LMU18CHV 10 82 82 - - 164
LMU24CHV 10 82 82 82 - 246.1
LMU36CHV 10 82 82 82 82 246.1
1
Kit contains two Y-branches: one for liquid and one for vapor.
Table 107:Multi F Outdoor Unit Refrigerant Piping System Limitations.
Component
Size (Inches)
1/4 3/8 1/2 5/8 3/4
Elbow (ft.)
0.5 0.6 0.7 0.8 1.2
Y-Branch Kit (ft., Multi F MAX systems
only)
1
1.6
Branch Distribution Unit (ft., Multi F
MAX systems only)
8.2
Field-supplied elbows are allowed as long as they are designed for
use with R410A refrigerant. The designer, however, should be cau-
tious with the quantity and size of fittings used, and must account for
the additional pressure losses in equivalent pipe length calculation
for each branch. The equivalent pipe length of each elbow must be
added to each pipe segment.
Using Refrigerant Components
The following are examples of manual pipe size calculations. Designers are highly encouraged to use LATS for Multi F systems.
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.
192 | DESIGN & PRACTICES
Multi F and Multi F MAX Indoor Unit Engineering Manual
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