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18
REFRIGERANT LINES
General Refrigerant Line Sizing:
1 The outdoor units are shipped with a full charge of R410A
refrigerant. All charges, line sizing, and capacities are based
on runs of 25 ft. (7.6 m). For runs over 25 ft. (7.6 m)
consult long−line section for proper charge adjustments.
2 Minimum refrigerant line length between the indoor and
outdoor units is 10 ft. (3 m).
3 Refrigerant lines should not be buried in the ground. If it is
necessary to bury the lines, not more than 36−in (914 mm)
should be buried. Provide a minimum 6−in (152 mm)
vertical rise to the service valves to prevent refrigerant
migration.
4 Both lines must be insulated. Use a minimum of 1/2−in.
(12.7 mm) thick insulation. Closed−cell insulation is
recommended in all long−line applications.
5 Special consideration should be given to isolating
interconnecting tubing from the building structure. Isolate
the tubing so that vibration or noise is not transmitted into
the structure.
IMPORTANT:
Both refrigerant lines must be insulated separately.
Table 15 lists the maximum lengths allowed.
Table 15—Piping and Refrigerant Information
SYSTEM SIZE
9K
12K
9K
12K
18K
24K
30K
V-Ph-Hz
115-1-60
208/230-1-60
Piping
Min. Piping Length
ft(m)
10(3)
10(3)
10(3)
10(3)
10(3)
10(3)
10(3)
Standard Piping Length
ft(m)
25(7.5)
25(7.5)
25(7.5)
25(7.5)
25(7.5)
25(7.5)
25(7.5)
Max. outdoor-indoor
height difference
ft(m)
32(10)
32(10)
32(10)
32(10)
65(20)
65(20)
82(25)
Max. Piping Length with
no additional refrigerant
charge
ft(m)
26(8)
26(8)
26(8)
26(8)
26(8)
26(8)
26(8)
Max. Piping Length
ft(m)
82(25)
82(25)
82(25)
82(25)
98(30)
98(30)
164(50)
Additional refrigerant
charge (between Standard
– Max piping length)
Oz/ft(g/m)
0.16(15)
0.16(15)
0.16(15)
0.16(15)
0.16(15)
0.32(30)
0.32(30)
Gas Pipe
(size - connection type)
in(mm)
3/8(9.52)
1/2(12.7)
3/8(9.52)
1/2(12.7)
1/2(12.7)
5/8(16)
5/8(16)
Liquid Pipe
(size - connection type)
in(mm)
1/4(6.35)
1/4(6.35)
1/4(6.35)
1/4(6.35)
1/4(6.35)
3/8(9.52)
3/8(9.52)
Refrigerant
Refrigerant Type
--
R410A
R410A
R410A
R410A
R410A
R410A
R410A
Charge Amount
Lbs(kg)
2.76(1.25)
2.76(1.25)
2.76(1.25)
2.76(1.25)
4.19(1.90)
5.18(2.35)
6.62(3.00)
S
The above charge is for piping runs up to 25 ft. (7.6 m).
S
For piping runs greater than 25 ft. (7.6 m), add refrigerant up to the allowable length as specified below.
S
The outdoor unit has an electronic expansion valve to manage the refrigerant flow of the connected fan coil.
Long Line Applications,:
1 No change in line sizing is required.
2 Add refrigerant per Table 16.
Table 16—Additional Charge Table
Unit Size
Total Line Length Ft (m)
Additional Charge, oz/ft. Ft (m)
Min.
Max.
10-25
(3-8)
>25-82
(8-25)
>82-98
(25-30)
>98-164
(30-50)
9
10 (3)
82 (25)
None
0.16
12
18
98 (30)
0.16
24
0.32
0.32
30
164 (50)
0.32