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Page 8
IM 796
Refrigerant Tubing
Tubing Length & Elevation
Copper tubing to connect the indoor and outdoor units is sup-
plied by others or it can be ordered from the factory. See
Table 1 for requirements. Cover both tubes individually with
3/8" wall foam insulation.
Table 1: Refrigeration Tubing Requirements
Note: The refrigerant pre-charged in the outdoor unit is for tubing length up to 25
ft. See Table 5, page 16 for additional R-22 refrigerant required on longer runs.
Figure 9. Tubing length and elevations
Tubing Preparation
•
Do not use contaminated or damaged copper tubing. Do
not remove plastic, rubber plugs and brass nuts from the
valves, fittings, tubings and coils until you are ready to
connect suction or liquid line into valves or fittings.
•
If any brazing work is required, ensure that the nitrogen
gas is passed through coil and joints while the brazing
work is done. This will eliminate soot formation on the
inside wall of the copper tubing.
•
Cut the copper tubing with a tube cutter.
See Figure 10
.
•
Remove burrs from cut ends by holding tubing down-
wards to prevent metal chips from entering the tubing.
•
Slide the flare nuts, for both the indoor unit and outdoor
unit onto the copper tubing.
•
Flare the tubing as shown in
Figure 10
,
Figure 11 and
Table 2
.
•
The flare must be even and not cracked or scratched.
Figure 10. Cutting and Flaring Tube
Table 2: Tube Flaring Dimensions
Tubing Connection To Units
•
Connect the copper tubing to both the indoor and outdoor
units.
See Figure 11
.
•
Torque each flare nut to specifications.
See Table 3
.
•
Cover both tubes individually with 3/8" minimum wall
foam insulation.
Table 3: Flare Nut Torque Specifications
Figure 11. Flare Tubing Connections
Model
10
15
20
25
Maximum length, ft., L
40
40
50
50
Max. elevation, ft., H
16
16
26
26
Max. number of bends
10
10
10
10
Liquid tube size - OD
1/4"
1/4"
1/4"
3/8"
Gas tube size - OD
3/8"
1/2"
5/8"
5/8"
Outdoor Unit
Indoor Unit
Tube Diameter - OD
X (in.)
Inch
Imperial
Rigid
1/4
.051
.028
3/8
.063
.039
1/2
.075
.051
5/8
.087
.067
Tube Size (in.)
Torque (ft./lb.)
1/4
13.3
3/8
31.0
1/2
40.6
5/8
48.0
Cutting Copper Tube
1/4 Tube
Copper Tube
Flaring Tool
X
See Table 2.
Flared Tube
Flare Nut
Unit Fitting