3-WAY Multi Models
Table 2-1 Refrigerant tubing length and range of rise/fall
Capacity proportion of the indoor units to the outdoor unit
Minimum capacity of indoor units that can be connected
Maximum number of indoor units (systems) that can be connected
Maximum allowable tubing length (L)
Difference between longest and shortest tubing lengths after the
No. 1 branch (fi rst branching point)
Maximum length of each tube branch
Maximum allowable height difference
between indoor and outdoor units
Maximum allowable height difference between indoor units
Maximum length from the fi rst T-tee to the last T-tee
(*1) The minimum length of tubes between outdoor units and indoor units is 7 m.
(*2) If cooling mode is expected to be used when the external temperature is 10°C or below, install so the
maximum length is 30 m.
(*3) Install so that the height difference between indoor units after the fi nal branch is within the limits shown in
Fig 3.
Outdoor unit
3-tube line (discharge gas tube, suction gas tube, liquid tube)
2-tube line (gas tube, liquid tube)
Indoor unit
External electric
valve kit
Solenoid
valve kit
D1
First branch
(Branch line)
H1
D2
Solenoid
valve kit
Indoor unit
Maximum height differential of indoor units after fi nal branch
Height difference between indoor units after the fi nal branch must be less than 4 m.
Indoor unit
If outdoor unit is above
If outdoor unit is below
d21
d22
Dn
Header
Maximum allowable tubing length L1 ≤ 120 m
L2 (Maximum length after fi rst branch)
D3
d2
d1
d3
4 m or less
Fig. 6 Length of Refrigerant Tubing
EN - 7
45.0 kW
50 - 200 %
≤ 22 type (equivalent to 0.8 horsepower)
24
≤ 120 m (equivalent length ≤ 145 m)
L
1
≤ 30 m
L
- L
2
8
≤ 30 m
ℓ1, ℓ2...ℓ8
≤ 50 m
H
1
≤ 35 m
H
(*2)
2
≤ 15 m
H
(*3)
3
≤ 2 m
L
3
CAUTION : 1) Each indoor unit requires a solenoid valve kit.
2) Never branch the tube between a solenoid valve kit and indoor unit.
3) Never branch the tube again after the header branching.
4) If using an external electric valve kit, install it between the solenoid
valve kit and the indoor unit.
d23
d24
Maximum length of each
branch tube
d ≤ 30 m
H2 (Height difference between indoor units)
≤ 15 m
L5
L4
d5
d4
If height difference between indoor units after the fi nal branch cannot be less than 4 m,
divide the height difference between upper and lower units (2 to 1).
56.0 kW
71.0 kW
(*1)
Externally mounted solenoid valve kit (sold separately)
Solenoid valve kit (purchased separately)
Branch tube (purchased separately)
Ball valve (purchased separately)
T-tee (provided by installer)
Closed (pinch) weld
Header (purchased separately)
2X m or
more
More than 4 m
X m