4
REFRIGERANT CHARGE ADJUSTMENTS
Liquid Line Size
R---410A Charge oz/ft (g/m)
3/8
0.60 (17.74)
(Factory charge for lineset = 9 oz / 266.16 g)
5/16
0.40 (11.83)
1/4
0.27 (7.98)
Units are factory charged for 15 ft (4.6 m) of 3/8” liquid line. The factory charge for 3/8” lineset 9 oz (266.16 g). When using other length
or diameter liquid lines, charge adjustments are required per the chart above.
Charging Formula:
[(Lineset oz/ft x total length) – (factory charge for lineset)] = charge adjustment
Example 1:
System has 15 ft of line set using existing 1/4“ liquid line. What charge adjustment is required?
Formula:
(.27 oz/ft x 15ft) – (9 oz) = (-4.95) oz.
Net result is to remove 4.95 oz of refrigerant from the system
Example 2:
System has 45 ft of existing 5/16” liquid line. What is the charge adjustment?
Formula:
(.40 oz/ft. x 45ft) – (9 oz.) = 9 oz.
Net result is to add 9 oz of refrigerant to the system
LONG LINE APPLICATIONS
An application is considered Long Line, when the refrigerant level in the system requires the use of accessories to maintain acceptable
refrigerant management for systems reliability. See Accessory Usage Guideline table for required accessories. Defining a system as long line
depends on the liquid line diameter, actual length of the tubing, and vertical separation between the indoor and outdoor units.
For Air Conditioner systems, the chart below shows when an application is considered Long Line.
AC WITH R--410A
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REFRIGERANT LONG LINE DESCRIPTION ft (m)
Beyond these lengths, long line accessories are required
Liquid Line Size
Units On Same Level
Outdoor Below Indoor
Outdoor Above Indoor
1/4
No accessories needed within allowed
lengths
No accessories needed within allowed
lengths
175 (53.3)
5/16
120 (36.6)
50 (15.2) vertical or 120 (36.6) total
120 (36.6)
3/8
80 (24.4)
35 (10.7) vertical or 80 24.4) total
80 (24.4)
Note:
See Long Line Guideline for details
VAPOR LINE SIZING AND COOLING CAPACITY LOSS
Acceptable vapor line diameters provide adequate oil return to the compressor while avoiding excessive capacity loss. The suction line
diameters shown in the chart below are acceptable for AC systems with R--410A refrigerant:
Vapor Line Sizing and Cooling Capacity Losses — R--410A
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Refrigerant 1--Stage Air Conditioner Applications
Unit
Nominal
Size (Btuh)
Maximum
Liquid Line
Diameters
(In. OD)
Vapor Line
Diameters
(In. OD)
Cooling Capacity Loss (%)
Total Equivalent Line Length ft. (m)
26---50
(7.9---15.2)
51---80
(15.5---24.4)
81---100
(24.7---30.5)
101---125
(30.8---38.1)
126---150
(38.4---45.7)
151---175
(46.0---53.3)
176---200
(53.6---61.0)
201---225
(61.3---68.6)
226---250
(68.9---76.2)
018
1 Stage
AC with
R---410A
3/8
1/2
1
2
3
5
6
7
8
9
11
5/8
0
1
1
1
2
2
2
3
3
3/4
0
0
0
0
1
1
1
1
1
024
1 Stage
AC with
R---410A
3/8
5/8
0
1
2
2
3
3
4
5
5
3/4
0
0
1
1
1
1
1
2
2
7/8
0
0
0
0
0
1
1
1
1
030
1 Stage
AC with
R---410A
3/8
5/8
1
2
3
3
4
5
6
7
8
3/4
0
0
1
1
1
2
2
2
3
7/8
0
0
0
0
1
1
1
1
1
036
1 Stage
AC with
R---410A
3/8
5/8
1
2
4
5
6
8
9
10
12
3/4
0
1
1
2
2
3
3
4
4
7/8
0
0
0
1
1
1
1
2
2
048
1 Stage
AC with
R---410A
3/8
3/4
0
1
2
3
4
5
5
6
7
7/8
0
0
1
1
2
2
2
3
3
1 1/8
0
0
0
0
0
0
0
1
1
060
1 Stage
AC with
R---410A
3/8
3/4
1
2
4
5
6
7
9
10
11
7/8
0
1
2
2
3
4
4
5
5
1 1/8
0
0
0
1
1
1
1
1
1
Applications in this area may be long line and may have height restrictions. See the
Residential Piping and Long Line Guideline
.
PA
13N
AZ