2WAY VRF SYSTEM
Control Functions
1
- 4
1
2
3
4
5
6
7
8
9
2. Selecting Outdoor Unit for Operation
2WAY VRF SYSTEM
Control Functions
2. Selecting Outdoor Unit for Operation
Cooling operation
Outdoor
temperature
118.4°F (48°C)
109.4°F (43°C)
There are two patterns of operation.
One is that the operation continues to run until the last one outdoor unit runs due to the detected outdoor
temperature and the other is that all outdoor units stop simultaneously.
Heating operation
Operation continues to run until the last outdoor unit remains in the operating mode.
All outdoor units stop simultaneously in the operating range of all outdoor units.
The inverter compressor mounted in the outdoor unit which continues to run until the end is short operating
time. The priority order of this inverter compressor is higher than that of other outdoor unit.
(3) Outdoor Unit Stop Rules
1. Stopping of all outdoor units
When all outdoor units must stop, all units will stop in order of unit No. every one second.
2. Stopping of individual outdoor units
When it is necessary to reduce the number of operating compressors due to load reduction of indoor units,
the outdoor units will stop in order of priority for the compressors. All outdoor units stop when all compressors
installed in the outdoor units stop.
The outdoor unit which operates continuously until the end installs the highest priority order of compressor in it.
59°F (15°C)
50°F (10°C)
Operating range in
all outdoor units
Operating range in
all outdoor units
Operating range in each
inverter compressor
*1
*2
*2
When starting at 109.4°F (43°C) - 118.4°F (48°C),
operation starts from all outdoor operating
ranges.
*1
When starting at 50°F (10°C) - 59°F (15°C),
operation starts from all outdoor operating
ranges.
3. Compressor Control
(1) Compressors Mounted in the Outdoor Units
(2) Compressor Selection Rules
Placement of compressor seen from the top
1. Priority order of compressors
A.
A
B
C
D
Decide first priority order of compressor in each outdoor unit.
B. Priority order of compressor trip counter = 0 is higher than that of compressor trip counter = 1.
C. Inverter compressor: Shorter operating time > Longer operating time
D. Compressor that “outdoor unit small address”
installed in outdoor unit
Compressor that “outdoor unit large address”
installed in outdoor unit
First priority order of inverter compressor in each outdoor unit > Other inverter compressor
Compressor trip counter =0 > Compressor trip counter =1
Shorter operating time > Longer operating time
“Outdoor unit small address”
installed in outdoor unit
“Outdoor unit large address”
installed in outdoor unit
>
>
*1
*1 Select first priority order of compressor in each outdoor unit by following method.
The compressor that has no trip counter, shorter operating time and smaller number of compressor will be
taken first priority.
First priority order of inverter compressor in each outdoor unit > Other inverter compressor
2WAY VRF SYSTEM
Control Functions
Type 72, 96
Type 120, 144
Front side
1st compressor
2nd compressor
1st compressor
Front side
Compressor trip counter =0 > Compressor trip counter =1
Shorter operating time > Longer operating time
1st compressor > 2nd compressor
Priority order flow of all compressors
Priority order flow of each outdoor unit
SM830237-07_北米向け2WAY_VRF.indb 4
18/06/19 18:55:30
