4
The suction line must always be insulated. DO NOT allow the
Liquid Line and Suction Line to come in direct (metal to metal)
contact.
Using suction line larger than shown in chart will result in poor oil
return and is not recommended.
For example: the system capacity published in AHRI is 17800
Btu/h. This data is based on the AHRI test condition and 25 feet
line set with standard suction tube size (3/4" tube). If you need to
add the line set more than 25 feet or use the optional suction
tube size, you need to recalculate the capacity with the
coefficient in the table. For 50 feet line and 5/8" suction tube, the
capacity will be 17800*0.97=17266 Btu/h.
5. Refrigerant line considerations
5.1 Service valve connection sizes
5.2 Refrigerant line sizes
5.3 Refrigerant piping limits and required refrigerant
line length
5.4 Refrigerant line insulation
Figure 8
Table 2
Table 3
Table 4
Table 5 Suction line length/size VS capcaity multiplier
Determine required line length and lift. You will need this later in Section
14.
Line Length
Figure 9
Total Line Length = __________ Feet.
Total vertical Change(Lift) = __________ Feet.
Model
Suction line
connection
Liquid line
connection
18
3/4
3/8
24
3/4
3/8
30
3/4
3/8
36
3/4
3/8
42
3/4
3/8
48
7/8
3/8
60
7/8
3/8
optional
standard
optional
standard
18
5/8
3/4
5/16
3/8
24
5/8
3/4
5/16
3/8
30
5/8
3/4
5/16
3/8
36
5/8
3/4
5/16
3/8
42
5/8
3/4
5/16
3/8
48
3/4
7/8
1/2
3/8
60
7/8
1-1/8
1/2
3/8
Suction line
Liquid line
Model
25
50
75
100
125
150
5/16
25
50
60
58
40
30
3/8
25
50
60
60
40
30
5/16
25
36
29
23
16
9
3/8
25
50
60
60
40
30
5/16
25
49
38
27
17
6
3/8
25
50
60
60
40
30
5/16
25
50
37
22
7
N/A
3/8
25
50
60
60
40
30
5/16
25
23
4
N/A
N/A
N/A
3/8
25
50
43
36
30
24
1/2
25
50
56
55
40
30
3/8
25
46
38
30
22
15
1/2
25
50
60
60
40
30
3/8
25
50
56
44
32
20
Total equivalent length(Feet)
18
24
Model
Liquid line
(Inches)
Maximum vertical length(Feet)
30
36
42
48
60
25
50
100
150
5/8
1.00
0.97
0.94
0.90
3/4
1.00
0.98
0.95
0.92
5/8
1.00
0.97
0.94
0.90
3/4
1.00
0.98
0.95
0.92
5/8
1.00
0.97
0.94
0.90
3/4
1.00
0.98
0.96
0.93
5/8
1.00
0.97
0.94
0.90
3/4
1.00
0.99
0.97
0.96
5/8
1.00
0.98
0.95
0.91
3/4
1.00
0.98
0.97
0.96
3/4
1.00
0.98
0.95
0.92
7/8
1.00
0.98
0.97
0.96
7/8
0.99
0.98
0.94
0.90
1-1/8
1.00
0.99
0.98
0.97
18
24
30
36
42
48
60
Model
Suction line
(Inches)
Coefficient
Total suction line length(Feet)
