Refrigerant Piping - Trane CyberAir DX Installation, Operation And Maintenance Manual

Perimeter precision air conditioners 21-105 kw / 60 hz
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Installation
side panel. For special piping requirements contact
product support.
If piping is brought into the side of the cabinet, ensure
adequate working space is available on that side or cut a
service opening into the adjacent wall if the unit is installed
in a corner.
The piping should be isolated by the use of vibration
isolating supports. Provide supports (clamps or hangers)
as necessary every 5 to 10 feet along piping runs to
minimize vibration and noise transmission. To reduce
vibration transmission and prevent pipe damage, seal
openings in walls using a soft, flexible material to pack
around the piping. After the piping is installed, seal the
gaps between the pipes and the cabinet entrance holes so
air won't leak around the pipes.
For pipe connection sizes, see the installation drawing
provided with your unit. Field piping is not necessarily the
same size as the unit's pipe connections.

Refrigerant Piping

Self-Contained Systems
No refrigeration connections are required for self-
contained water or water/glycol cooled systems.
Split Systems
Split air-cooled systems with a remote condenser will
require field installed refrigeration piping. All split
systems are shipped with a dry nitrogen holding charge of
100 psig. Release the pressure via an available stem valve
or Schrader valve prior to uncapping the pipes.
Do not release the pressure until the field installed
refrigerant piping is ready to connect.
Split systems utilizing a remote condenser will require a
copper discharge and copper liquid line for each
compressor circuit. The following instructions should be
followed to ensure proper installation. A/C systems,
utilizing R-410A refrigerant, have higher operating
pressures than systems utilizing R-407C.
All refrigeration piping should be installed with high
temperature brazed joints suitable for R-410A refrigerant.
Use standard refrigeration practices for piping supports,
leak testing, dehydration and charging of the refrigeration
circuits. Oil traps must be included every 20 feet in the
vertical risers and the refrigerant lines must be sloped ¼
inch for every 10 feet in the horizontal lines to ensure
proper oil return to the compressor.
Wrap wet rags around the pipes between the areas to be
soldered and any nearby refrigeration components to
keep excessive heat from traveling through the pipe and
causing damage. Clear all pipe connections of debris and
prepare the connections for soldering. Use only "L" or "K"
grade refrigerant copper piping. Be careful not to allow
solder/piping debris to get inside refrigerant lines. Silver
solder containing a minimum of 15% silver is
recommended. Dry nitrogen should be flowing through
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the tubing while soldering at a rate of not less than 1-2 CFM
(.03 -.06 M3/minute).
Refrigerant lines for split systems must be sized according
to the piping distance between the evaporator and the
condenser(s). Each valve, fitting and bend in the
refrigerant line must be considered in this calculation.
Pipe sizes are given for "equivalent feet", not linear feet. Do
not confuse the terminologies. For example, a 7/8 inches
standard 90° elbow has an equivalent length of 1.5 feet; a
7/8 inches branch Tee has an equivalent length of 3.5 feet.
These corrections must be accounted for when sizing your
piping. Refer to the following table for determining the
standard equivalent lengths, in feet, of straight pipe.
Table 1.
Standard equivalent lengths of straight pipe
Equivalent Length (ft) of Straight Pipe
OD (In.)
Globe
Angle
Line Size
Valve
Valve
9.0
5.0
1/2
12
6.0
5/8
15
8.0
7/8
22
12
1-1/8
28
15
1-3/8
35
17
1-5/8
45
22
2-1/8
51
26
2-5/8
65
34
3-1/8
80
40
3-5/8
If the condenser is installed above the evaporator, the
discharge line should include a p-trap at the lowest point
in the piping. The highest point in the discharge line
should be above the condenser coil and should include an
inverted trap to help prevent oil and liquid from flooding
back to the compressor during off cycles.
If the condenser is installed below the evaporator, an
inverted trap the height of the evaporator coil is required
on the liquid line to help prevent oil and liquid from
flooding back to the compressor during off cycles.
Important:
Discharge and liquid line lengths should not
exceed 150 equivalent feet.
Note: Ensure proper condenser selection in order to
maintain reasonable sub-cooling temperatures.
Refer to the remote condenser IOM manual, supplied with
the equipment, for detailed installation instructions.
Refer to the following refrigerant line size tables for
recommended line sizing.
Note: In the following tables, the line sizes are for
individual refrigeration circuits. CyberAir- DX units
must have two separate pairs of refrigeration lines.
(One per compressor circuit.)
90º
45º
Tee
Tee
Elbow
Elbow
Line
Branch
0.9
0.4
0.6
2.0
1.0
0.5
0.8
2.5
1.5
0.7
1.0
3.5
1.8
0.9
1.5
4.5
2.4
1.2
1.8
6.0
2.8
1.4
2.0
7.0
3.9
1.8
3.0
4.6
2.2
3.5
5.5
2.7
4.5
6.5
3
5.0
SS-SVX002B-EN
10
12
15
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