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6
SYSTEM REQUIREMENTS
Allow sufficient space for airflow and unit servicing. See Fig. 22 through 26 for the minimum required clearances.
Piping
IMPORTANT: Both refrigerant lines must be insulated separately.
The minimum refrigerant line length between the indoor and outdoor units is 10 ft. (3m). See Table 11 for the maximum lengths.
Table 11—Maximum Piping Lengths
Outdoor Unit
System Size
18
24
30
36
42
48
56
Piping
Min. Piping Length
ft
10
10
10
10
10
10
10
Standard Piping Length
ft
32
98
131.2
131.2
131.2
98.42
98.42
Max. outdoor-indoor height difference
ft
33
33
49.2
49.2
49.2
98.42
98.42
Max. height distance between indoor and indoor
ft
33
33
24.6
24.6
24.6
49.21
49.21
Max. height distance between indoor and outdoor and indoor
ft
32
32
49.2
49.2
49.2
98.42
98.42
Max. height distance between indoor and outdoor and outdoor up
ft
33
33
49.2
49.2
49.2
98.42
98.42
Max. equivalent piping outdoor to last indoor
ft
33
65
82
82
82
229
229
Max. Piping Length with no additional refrigerant charge
ft
32
98
131.2
131.2
131.2
98.42
98.42
Max. Piping Length
ft
65
196
229.7
246
246
442.9
475.7
Gas Pipe (size - connection type)
in
3/8
3/8
3/8
3/8
3/8
5/8
5/8
Liquid Pipe (size - connection type)
in
1/4
1/4
1/4
1/4
1/4
3/8
3/8
Refrigerant
Refrigerant Type
R-410A
R-410A
R-410A
R-410A
R-410A
R-410A
R-410A
Heat Pump Models Charge Amount
Lbs
3.53
4.85
6.17
8.05
8.05
10.91
10.91
NOTE: Tables 12 through 16 display the piping size specifications.
Table 12—Indoor Unit Piping Connection High Wall
Indoor High Wall
(40GRQ)
SIZE
9
12
18
Pipe Connection Size - Liquid
in
1/4"
1/4"
1/4"
Pipe Connection Size - Suction
in
1/2"
1/2"
5/8"
Table 13—Indoor Piping Connection High Wall
Indoor High Wall
(40GJB)
SIZE
9
12
18
24
Pipe Connection Size - Liquid
in
1/4"
1/4"
1/4"
1/4"
Pipe Connection Size - Suction
in
1/2"
1/2"
5/8"
5/8"
Table 14—Indoor Piping Connection Cassette
Indoor Cassette
SIZE
12
18
24
Pipe Connection Size - Liquid
in
1/4"
1/4"
3/8"
Pipe Connection Size - Suction
in
3/8"
1/2"
5/8"
Table 15—Indoor Piping Connection Ducted
Indoor Ducted
SIZE
9
12
18
21
24
Pipe Connection Size - Liquid
in
1/4"
1/4"
1/4"
3/8"
3/8"
Pipe Connection Size - Suction
in
3/8"
3/8"
1/2"
5/8"
5/8"
Table 16—Indoor Piping Connection Floor Console
Indoor Floor Console
SIZE
9
12
18
Pipe Connection Size - Liquid
in
1/4"
1/4"
1/4"
Pipe Connection Size - Suction
in
3/8"
3/8"
1/2"
Table 17—Additional Refrigerant Charge
TOTAL LINE
LENGTH ft.
ADDITIONAL CHARGE, 1/4” LIQUID LINE / 3/8” LIQUID LINE, oz/ft. ft. (m)
Unit
Size
Min
Max
10-32
(3-10)
>32-66
(10-20)
>66-98
(20-30)
>98-131.2
(30-40)
>131.2-196
(40-60)
>196-230
(60-70)
>230-246
(70-75)
>246-443
(75-135)
>443-476
(135-145)
18
10
66
None
0.20 / 0.20
24
10
196
None
None
0.20 / 0.20
0.20 / 0.20
30
10
230
None
None
None
0.24 / 0.58
0.24 / 0.58
36
10
246
None
None
None
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
42
10
246
None
None
None
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
48
10
443
None
None
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
56
10
476
None
None
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
0.24 / 0.58
Additional Refrigerant Calculation Sizes 30K, 36K and 42K:
Sum Total Liquid Pipe 1/4” (ft.) x 0.24 + Sum Total Liquid Pipe 3/8” (ft.) x 0.58 – 31 oz
Additional Refrigerant Calculation Sizes 48K and 56K:
Sum Total Liquid Pipe 1/4” (ft.) x 0.24 + Sum Total Liquid Pipe 3/8” (ft.) x 0.58 – 51.7 oz
NOTE: If the calculation results in a negative number no additional refrigerant is required.
NOTES
:
EXV = Electronic Expansion Device
Electronic expansion valves in the outdoor unit are used as metering devices.