13
7.4 Tubing Installation
Observe the following when installing correctly sized type “L” refrigerant tubing
between the condensing unit and evaporator coil:
•
If a portion of the liquid line passes through a hot area where liquid refrigerant
can be heated to form vapor, insulating the liquid line is required.
•
Use clean, dehydrated, sealed refrigeration grade tubing.
•
Always keep tubing sealed until tubing is in place and connections are to be
made.
•
Blow out the liquid and vapor lines with dry nitrogen before connecting to the
outdoor unit and indoor coil. Any debris in the line set will end up plugging the
expansion device.
•
As an added precaution, a high quality filter drier is standard on R-410A units.
•
Do not allow the vapor line and liquid line to be in contact with each other. This
causes an undesirable heat transfer resulting in capacity loss and increased
power consumption. The vapor line must be insulated.
LIQUID LINE SIZE - OUTDOOR UNIT ABOVE INDOOR COIL
R-410A
System
Capacity
Model
Line Size
Connection
Size (Inch
I.D.) [mm]
Line Size
(Inch O.D.)
[mm]
Minimum
Vertical Separation - Feet [m]
1/4” [6.35]
0
1 [0.31]
24 [7.32]
50 [15.24]
76 [23.17]
102 [31.09]
-024
3/8” [9.53]
5/16” [7.93]*
0
0
0
0
0
0
3/8” [9.52]
0
0
0
0
0
0
5/16” [7.93]
0
0
0
5 [1.52]
13 [3.96]
20 [6.10]
-036
3/8” [9.53]
3/8” [9.52]*
0
0
0
0
0
0
1/2” [12.70]
0
0
0
0
0
0
5/16” [7.93]
0
0
0
7 [2.13]
28 [8.53]
50 [15.24]
-048
3/8” [9.53]
3/8” [9.52]*
0
0
0
0
0
0
1/2” [12.70]
0
0
0
0
0
0
3/8” [9.52]*
0
0
0
0
0
0
-060
3/8” [9.53]
1/2” [12.70]
0
0
0
0
0
0
25 [7.62]
50 [15.24]
75 [22.86]
100 [30.48]
125 [38.1]
150 [45.72]
Liquid Line Size
Outdoor Unit
Above
Indoor Coil (Cooling Only - Does not apply to Heat Pumps)
Total
Equivalent
Length - Feet [m]
LIQUID LINE SIZE - OUTDOOR UNIT BELOW INDOOR COIL
R-410A
System
Capacity
Model
Line Size
Connection
Size (Inch
I.D.) [mm]
Line Size
(Inch O.D.)
[mm]
Maximum
Vertical Separation - Feet [m]
1/4” [6.35]
13 [3.96]
N/A
N/A
N/A
N/A
N/A
-024
3/8” [9.53]
5/16” [7.93]*
25 [7.62]
21 [6.40]
17 [5.18]
13 [3.96]
9 [2.74]
N/A
3/8” [9.52]
25 [8.23]
26 [7.93]
25 [7.62]
23 [7.01]
22 [6.71]
20 [6.10]
5/16” [7.93]
15 [4.57]
N/A
N/A
N/A
N/A
N/A
-036
3/8” [9.53]
3/8” [9.52]*
19 [5.79]
17 [5.18]
15 [4.57]
12 [3.66]
10 [3.05]
N/A
1/2” [12.70]
21 [6.40]
21 [6.40]
20 [6.10]
20 [6.10]
19 [5.79]
19 [5.79]
5/16” [7.93]
25 [9.14]
17 [5.18]
N/A
N/A
N/A
N/A
-048
3/8” [9.53]
3/8” [9.52]*
25 [11.89]
34 [10.36]
30 [9.14]
25 [7.62]
21 [6.40]
17 [5.18]
1/2” [12.70]
25 [12.80]
41 [12.50]
41 [12.50]
40 [12.19]
39 [11.89]
38 [11.58]
3/8” [9.52]*
25 [17.98]
49 [14.94]
40 [12.19]
30 [9.14]
20 [6.10]
10 [3.05]
-060
3/8” [9.53]
1/2” [12.70]
25 [19.51]
50 [18.90]
61 [18.59]
60 [18.29]
59 [17.98]
57 [17.37]
25 [7.62]
50 [15.24]
75 [22.86]
100 [30.48]
125 [38.1]
150 [45.72]
Liquid Line Size
Outdoor Unit
Below
Indoor Coil (Cooling Only - Does not apply to Heat Pumps)
Total
Equivalent
Length - Feet [m]
TABLE 4
(-)ARL LIQUID LINE SIZING
NOTES:
N/A = Application Not Recommended
*Standard Line Size
NOTES:
N/A = Application Not Recommended
*Standard Line Size
