Install Instructions
Table Of Contents
15
Installation Manual
Due to our policy of continuous product innovation, some specifications may change without notification.  
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MA
X
MUL
TI 
F
MUL
TI 
F
GENERAL DATA
Typical Multi F/Multi F Max Systems
Max. 49.2 feet
Max. 24.6 feet
A
B
C
D
Typical Multi F System 
Example: LMU36CHV outdoor unit with four (4) 
indoor units connected.
ODU: Outdoor Unit.
IDU: Indoor Unit.
A, B, C, D: Piping from Outdoor Unit to Indoor Unit.
Major System Components
A typical Multi F system consists of an outdoor unit (ODU), refrigerant piping, and two (2) to four (4) indoor units (IDUs). The ceiling cassette 
units described in this manual are one of the types of IDUs that can be connected to a Multi F system.
A typical Multi F Max system consists of an ODU, refrigerant piping, one or two branch distribution units (BDU), and two (2) to eight (8) IDUs.  
The ceiling cassette units described in this manual are one of the types of IDUs that can be connected to a Multi F Max system.
Example: LMU540HV outdoor unit with four 
(4) indoor units, and one (1) branch distribu-
tion unit connected.
ODU: Outdoor Unit.
IDU: Indoor Unit.
BDU: Branch Distribution Unit.
A: Main Piping.
B: Branch Piping (Branch Distribution Unit to 
Indoor Unit[s]).
A
h2 ≤ 49.2 feet
h3 ≤ 32.8 feet
h1 ≤ 98.4 feet
BDU 
ODU 
IDU 
IDU 
IDU 
IDU 
B
B
B
B
Typical Multi F MAX System with One Branch Distribution Unit
Outdoor 
Unit
Minimum Length for Each 
Pipe Segment (ft.)
Maximum Equivalent Pipe Length 
to Each Indoor Unit (ft.)
Maximum Equivalent Pipe Length 
for Each System (ft.)
A B C D
LMU18CHV 9.8 82 82  - - 164
LMU24CHV 9.8 82 82 82 - 246.1
LMU30CHV 9.8 82 82 82 82 246.1
LMU36CHV 9.8 82 82 82 82 246.1
Table 7: Multi F Outdoor Unit Refrigerant Piping System Limitations.










