Interconnecting Tubing (cont.)
%XAMPLE A 3-Ton condensing unit is installed 50’
below the ID unit, requires a 5 of 12 diameter
liquid line, and 4 90° LR elbows.
• itting Equivalent Length (ft.) = 4 x .9 = 3.6’
• Total quivalent ength ft. 5 3.6 .6
R-410A
System
Capacity
Model
Liquid Line
Size
Connection
Size (Inch
I.D.) [mm]
Liquid Line
Size (Inch
O.D.) [mm]
Liquid Line Size
Elevation (Above or Below) Indoor Coil
Total
Equivalent
Length - Feet [m]
25 [7.62] 50 [15.24] 75 [22.86] 100 [30.48] 125 [45.72] 150 [45.72] 175 [53.34] 200 [60.96] 225 [68.58] 250 [76.20] 275 [83.82] 300 [91.44]
Maximum
Vertical Separation - Feet [m]
37 3/8" [9.53]
1/4 [6.35] 25 [7.62]
N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R N/R
5/16 [7.94] 25 [7.62] 50 [15.24] 60 [18.29] 45 [13.72] 35 [10.67] 20 [6.1] 5 [1.52]
N/R N/R N/R N/R N/R
3/8 [9.53] 25 [7.62] 50 [15.24] 75 [22.86] 80 [24.38] 80 [24.38] 75 [22.86] 70 [21.34] 65 [19.81] 60 [18.29] 55 [16.76] 50 [15.24] 45 [13.72]
7/16 [11.12] 25 [7.62] 50 [15.24] 75 [22.86] 95 [28.96] 90 [27.43] 90 [27.43] 85 [25.91] 85 [25.91] 85 [25.91] 80 [24.38] 80 [24.38] 80 [24.38]
1/2 [12.71] 25 [7.62] 50 [15.24] 75 [22.86] 95 [28.96] 95 [28.96] 95 [28.96] 95 [28.96] 95 [28.96] 95 [28.96] 90 [27.43] 90 [27.43] 90 [27.43]
This application is acceptable because the 50’
vertical rise is less than the maximum rise of 75’ for
this application. The application is also considered
to have a long line set. Reference the long line set
section of the I&O for detail.
Long Line Set Applications
ong line set applications are dened as ap-
plications that require accessories or alternate
construction methods. The following are special
considerations that need to be addressed when
installing a long line set application:
• Additional refrigerant charge
• itting losses and maximum equivalent length
considerations
• efrigerant migration during the o cycle
• il return to the compressor
• apacity losses
• System oil level adustment
Table 2 is used to determine if the application is
considered to have a long line set. The region of
the chart that is shaded grey is considered to
be a long line set application.
Oil Level Adjustments for
Long Line Set Applications
Additional oil will need to be added for long line set
applications. (Ref. Table 2). Below is the equation
for the oil level adjustment and the compressor
name plate oil charge for the dierent od units.
Oil to be Added = [(Charge Adjustment + OD
5NIT.AME0LATE#HARGEOZXn;
X#OMPRESSOR.AME0LATE/IL#HARGEOZ=
%XAMPLE An application requires 125ft of line set
with a liquid line diameter of 3, harge Adust-
ment = 52.4 oz., Name Plate Charge = 107 oz.,
Name Plate Oil Charge = 25 oz., Oil to be Added =
((52.4 oz. +107 oz.) x .022) – (.10 x 25 oz.) = 1.0 oz.
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