80
MUL
TI V 5 Outdoor Unit Installation Manual
Due to our policy of continuous product innovation, some specifications may change without notification.
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ODU
Capacity
(ton)
Standard Pipe Diameter
Pipe diameter when pipe length is ≥295 feet or when height
differential (ODU ↔ IDU) is >164 feet
Liquid Pipe
(inches OD)
Low Pressure Vapor
Pipe (inches OD)
High Pressure Vapor
Pipe (inches OD)
Liquid Pipe
(inches OD)
Low Pressure Vapor
Pipe (inches OD)
High Pressure Vapor
Pipe (inches OD)
6
3/8Ø
3/4Ø
5/8Ø
1/2Ø
No Increase
No Increase
8
3/8Ø
7/8Ø
3/4Ø
1/2Ø
No Increase
No Increase
10
1/2Ø
1-1/8Ø
3/4Ø
5/8Ø
No Increase
No Increase
12
1/2Ø
1-1/8Ø
7/8Ø
5/8Ø
No Increase
No Increase
14-16
5/8Ø
1-1/8Ø
7/8Ø
3/4Ø
No Increase
No Increase
18-20
5/8Ø
1-3/8Ø
1-1/8Ø
3/4Ø
No Increase
No Increase
22-28
3/4Ø
1-3/8Ø
1-1/8Ø
7/8Ø
No Increase
No Increase
30-42
3/4Ø
1-5/8Ø
1-1/8Ø
7/8Ø
No Increase
No Increase
Table 38: Main Pipe (A) Diameters from Outdoor Unit to First Y-branch.
Example: Triple-frame system, four (4) heat
recovery units, one (1) header, and twelve (12)
indoor units connected
ODU: Outdoor Units.
HRU: Heat Recovery Units.
IDU: Indoor units.
A: Main Pipe from Outdoor Unit to First Y-branch.
B: Heat Recovery Unit to Heat Recovery Unit,
Y-branch to Heat Recovery Unit, Heat Recovery Unit
to Header, or Y-branch to Y-branch.
C: Heat Recovery Unit / Header to Indoor Unit.
• Always reference the LATS Multi V software report.
• Larger-capacity outdoor units must be the master in a
multi-frame system.
• Master outdoor unit capacity must be greater than
or equal to the slave1 outdoor unit capacity, and,
where applicable, slave1 outdoor unit capacity must
be greater than or equal to the slave2 outdoor unit
capacity.
• Connection piping from branch to branch cannot ex-
ceed the main pipe diameter (A) used by the outdoor
unit.
• Install the header branches or heat recovery units
so that the pipe distances between the between the connected indoor units are minimized. Large differences in pipe distances can cause
indoor unit performances to fluctuate.
•
Y-branches and other header branches cannot be installed downstream of the initial header branch.
•
Total capacity of indoor units in series connection of heat recovery units ≤192,400 Btu/h.
• If large capacity indoor units (>12,000 Btu/h with piping sizes >5/8Ø / 3/8Ø) are installed, the valve group setting must be used. (Refer to
the PCB of the heat recovery unit for the valve group control setting.)
Case 1: Maximum height is 131 feet if installed with a Y-branch.
Case 2: Maximum height is 16 feet in heat recovery control unit series connection.
*
Elevation1
Elevation2
Master ODU
Slave1
ODU
Slave2
ODU
Case 1
Case 2
A
Y-branch (first)
B
C
Closest
IDU
C
HRU
C
C
B
B
C
C
C
C
B
B
C
C
x
Header
C
C
To Indoor Units
To
Outdoor Unit
Y-branch
height1
≤16-7/16 feet
B
Y-branch (second)
HRU
HRU
HRU
IDU
IDU
IDU
IDU
IDU
IDU
IDU
IDU
IDU
IDU
Farthest
IDU
Brazed
cap
49 feet
16 feet
Elevation3
Elevation4
Sample Layouts
INSTALLING FOR HEAT RECOVERY
OPERATION
Images are for illustrative purposes only and are not accurate representations. For specific details on piping limitations and other refrigerant system
rules, review the information in this entire piping section, see the Multi V 5 Engineering Manual, and follow the LATS diagram.
Sample Layouts
