Allied Air 4HP16LT Series Installation And Maintenance Instructions Manual page 5

WARNING
Polyol ester (POE) oils used with R410A
refrigerant absorb moisture very quickly. It is
very important that the refrigerant system be
kept closed as much as possible. DO NOT
remove line set caps or service valve stub
caps until ready to make connections.
Installing Refrigerant Line
During the installation of an air conditioning system, it is
important to properly isolate the refrigerant line to prevent
unnecessary vibration. Line set contact with the structure
(wall, ceiling, or floor) may cause objectionable noise
when vibration is translated into sound. As a result, more
energy or vibration can be expected. Close attention to
line set isolation must be observed.
Following are some points to consider when placing and
installing a high-efficiency outdoor unit:
Placement
Be aware that some localities are adopting sound ordinances
based on how noisy the unit is at the neighbor's home, not at
the original installation. Install the unit as far as possible from
the property line. When possible, do not install the unit
directly outside a bedroom window. Glass has a very high
level of sound transmission. Figure 4 shows how to place the
outdoor unit and line set to reduce line set vibration.
Outside Unit Placement
and Installation
Install unit away
from windows
Two 90° elbows installed in lineset
will reduce lineset vibration
Figure 4
506468-01
Line Set Isolation
Illustrations on pages 6 and 7 demonstrate procedures
which ensure proper refrigerant line set isolation. Figure 5
shows how to install line sets on horizontal runs. Figure 6
shows how to make a transition from horizontal to vertical.
Figure 7 shows how to install line sets on vertical runs.
Brazing Connection Procedure
1. Cut ends of refrigerant lines square (free from nicks
or dents). Debur the ends. The pipe must remain
round; do not pinch end of line.
2. Before making line set connections, use dry nitrogen to
purge the refrigerant piping. This will help to prevent
oxidation and the introduction of moisture into the system.
3. Use silver alloy brazing rods (5% or 6% silver alloy for
copper-to-copper brazing or 45% silver alloy for
copper-to-brass or copper-to-steel brazing) which are
rated for use with R410A refrigerant.
4. Remove the Schrader core assemblies before brazing
to protect them from damage due to extreme heat.
Replace the cores when brazing is complete.
5. Remove light maroon washers from service valves and
shield light maroon stickers to protect them during
brazing. Wrap a wet cloth around the valve body and
copper tube stub to protect it from heat damage.
6. Braze the line set to the service valve. Quench the joints
with water or a wet cloth to prevent heat damage to the
valve core and opening port. The tube end must stay
bottomed in the fitting during final assembly to
ensure proper seating, sealing, and rigidity.
7. Install a thermal expansion valve (which is sold
separately and which is approved for use with R410A
refrigerant) in the liquid line at the indoor coil (see
Refrigerant Metering Device on page 9).
Issue 1004
Page 5