reFrIGerant deSIGn | 47
Refrigerant Piping Design & Layout Best Practices
Due to our policy of continuous product innovation, some specifications may change without notification.
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LG Electronics U.S.A., Inc., Englewood Cliffs, NJ. All rights reserved. “LG ” is a registered trademark of LG Corp.
refrigerant Piping System Layout
Pipe Sleeves at Penetrations
LG requires that all pipe penetrations through walls, floors, and pipes buried underground be properly insulated and routed through an
appropriate wall sleeve of sufficient size to prevent compression of refrigerant pipe insulation and free movement of the pipe within the
sleeve. Underground refrigerant pipe shall be routed inside a protective sleeve to prevent insulation deterioration. Refer to Figure 24.
Figure 24: Pipe Sleeve options.
Diameter of penetrations shall be determined by pipe diameter plus the thickness of the insulation.
Underground refrigerant Piping
Refrigerant pipe installed underground should be routed inside a
vapor tight protective sleeve to prevent insulation deterioration and
water infiltration. Refrigerant pipe installed inside underground
casing must be continuous without any joints. Underground
refrigerant pipe must be located at a level
below the frost line
.
Figure 25: Typical Arrangement of Refrigerant Pipe and Cable(s) in a
Utility Conduit.
Table 21: Utility Conduit Sizes.
1
oD pipe diameter in inches; Values in parenthesis () indicate oD of pipe with insulation jacket.
2
Diameter of pipe with insulation. Thickness of pipe insulation is typical. Actual required thickness may
vary based on surrounding ambient conditions and should be calculated and specified by the design
engineer.
3
Insulation thickness (value in parenthesis) = 3/8 inch.
4
Insulation thickness (value in parenthesis) = 1 inch.
Liquid Pipe
1
Vapor Pipe
1
3/8 (1-1/8
2,3
)
1/2 (2.0
2,4
)
5/8 (2-1/8
2,4
)
1/4 (1.0)
3
4
4
4
3/8 (1-1/8)
3
4
4
4
Table 22: Heat Pump Unit Refrigerant Pipe Connections
(All Brazed Type).
Model
Liquid Conn.
(inches)
Vapor Conn.
(inches)
LSU090HSV4, LSU120HSV4
1/4
3/8
LSU180HSV4
3/8
5/8
inSTAllATion & lAyoUT beST PrAcTiceS
Vapor Line
Liquid Line
Min. 18 Gauge
Cable
Power/Communication
Pipe Sleeve
Insulation Material
Insulation
Material
