LGRED Installation Manual
34
MULTI F / MULTI F MAX with LGRED Outdoor Unit Installation Manual
Due to our policy of continuous product innovation, some specifications may change without notification.
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MULTI
F
MAX
MULTI
F
WITH
Table 12: Multi F MAX with LGRED 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 with
LGRED systems only)
1
1.6
Branch Distribution Unit (ft., Multi F
MAX with LGRED systems only)
8.2
Using Refrigerant Components
Field-supplied elbows are allowed as long as they are designed for
use with R410A refrigerant. The designer, however, must be cau-
tious with the quantity and size of fittings used, and must account
for the additional pressure losses in equivalent pipe length calcula-
tion for each branch. The equivalent pipe length of each elbow must
be added to each pipe segment.
Example of a Multi F MAX with LGRED System with Two Branch Distribution
Units
Example: LMU421HHV outdoor unit with six (6) indoor
units and two (2) branch distribution units connected.
ODU: Outdoor Unit.
IDU: Indoor Unit.
BD: Branch Distribution Unit(s).
A: Main Pipe.
B: Branch Pipe (Branch Distribution Unit[s] to Indoor Unit[s]).
Table 13: Multi F MAX with LGRED Piping Sizes.
Table 14: Equivalent Piping Length for Elbows, Y-branches, and Branch
Distribution Units.
Multi F MAX with LGRED Outdoor Unit Piping Length and Elevation
Limitations
5()5,*(5$176$)(7<67$1'$5'6
DEVICE CONNECTION LIMITATIONS
h1
C
Branch Pipe
Main Pipe
BD Unit
BD Unit
A
B
h2
Figure 23: Multi F MAX Refrigerant Piping
System Limitations.
Piping Main Pipe A (inch) Branch Pipe B
Liquid Ø3/8
Depends on the size
of the indoor unit piping
Gas Ø3/4
B
A
h2 IHHW
A
h3 IHHW
KIHHW
h1 IHHW
BDU Y-Branch
BDU
IDU
A
ODU
IDU
IDU
IDU
IDU
IDU
B
B
B
B
B
Pipe Length
(ELF = Equivalent
Length of pipe in
Feet)
7RWDOSLSLQJOHQJWKȉ$ȉ% IHHW
Main pipe (Outdoor
Unit to Branch Distri-
bution Units: A)
Minimum for Each (A)
Piping Segment
16.4 feet
0D[LPXPȉ$ IHHW
7RWDOEUDQFKSLSLQJOHQJWKȉ% IHHW
Branch pipe (Branch
Distribution Units to
Indoor Units: B)
Minimum 16.4 feet
Maximum IHHW
Elevation
Differential
(All Elevation
Limitations are
Measured in
Actual Feet)
If outdoor unit is above or below indoor unit (h1) IHHW
Between the farthest two indoor units (h2) IHHW
Between branch distribution unit and farthest
connected indoor unit(s) (h3)
IHHW
Between branch distribution units (h4) IHHW
Max. Combination
of IDUs
LMU361HHV = 48,000 LMU421HHV = 56,000 LMU480HHV = 65,000
1
.LWFRQWDLQVWZR<EUDQFKHVRQHIRUOLTXLGDQGRQHIRUYDSRU