Brazing; System Evacuation; Refrigerant Charging - Nordyne iQ Drive Installation Instructions Manual

• Refrigerant tubing should be supported in a manner
which assures that the tubing will not vibrate or wear as
a result of contact with sharp materials or edges during
system operation.
• Lines must be clean refrigeration-grade copper.
• Avoid removing caps and plugs from the condensing unit
or lines until they are ready to be connected.
• Insulate the vapor line with refrigerant line insulation ¼"
wall thickness or greater.
Proper system performance and oil management depend
on properly selecting the liquid and vapor line sizes. Refer
to Table III for the proper size of fi eld supplied lines. The
maximum allowable refrigerant line length is 100 ft.
Line Set
up to 24 ft. 25 to 39 ft. 40 to 75 ft.
Length
3/4 in. 7/8 in.
-024K Units
(19 mm) (22 mm)
7/8 in. 7/8 in.
-036K Units
(22 mm) (22 mm)
7/8 in. 7/8 in.
-048K Units
(22 mm) (22 mm)
Table III. Permissible Refrigerant Line Sizes
The maximum vertical elevation between the condensing unit
and indoor coil is 50 ft. Systems that require more elevation
will need to have an oil trap installed in the vapor line. Refer
to Nordyne Application Guideline for Refrigerant Lines Over
75 Feet (document 044B-0600) for piping details.
A fi lter drier is supplied with the unit. It is required and
recommended that it be installed near the indoor coil.
It is recommended to replace existing refrigerant lines that
were previously used for an R-22 system. If the lines are not
replaced, they must be properly fl ushed by a licensed EPA
certifi ed technician in accordance with the manufacturer's
instructions and established procedures.

Brazing

Use the appropriate safety equipment while brazing. Items
such as gloves, safety glasses, proper ventilation, and a fi re
extinguisher should be used.
1. Route the refrigerant lines from the indoor coil to the
service valves on the outdoor unit. Avoid sharp radius
bends and turns.
2. Make sure that the vapor line is properly insulated for the
entire length of the run for maximum system effi ciency.
Improper insulation may also create condensation and
result in water damage to the equipment and building
structure.
3. Remove the valve cores from the unit's service valves.
Wrap the valves completely with wet rags to protect them
Vapor Line
75 to 100 up to 100
ft.
7/8 in. 1 1/8 in.
(22 mm) (29 mm)
1 1/8 in. 1 1/8 in.
(29 mm) (29 mm)
1 1/8 in. 1 1/8 in.
(29 mm) (29 mm)
from overheating during the brazing operation.
4. Connect both the vapor and liquid lines. Tubes should be
round, de-burred and free of debris. Use a phosphorous
and copper or silver brazing alloy for the joints. Do not
use soft solder with a low melting point.
5. Connect the indoor lines according to the indoor unit
instructions. The indoor coil will require the same alloys
and wet rags to protect the sensors from excessive heat
on the refrigerant lines.
6. Allow the service valves to cool and replace the valve
cores.
7. Leak test the connections using low pressure dry
nitrogen.

System Evacuation

1. Connect the refrigerant gauge manifold to both the
Liquid
vapor and liquid service valves. See Figure 8. Connect
Line
the center port to the vacuum pump.
2. Open both manifold valves and start the vacuum pump.
ft.
After a short time, it is recommended to close the
manifold valves and stop the vacuum pump to look for
3/8 in.
a rapid loss of vacuum. Loss of vacuum indicates that
(10 mm)
there is a leak in the system. Repeat the leak test if
3/8 in.
required.
3. Evacuate the system to at least 500 microns to remove
(10 mm)
non-condensables and water vapor. Close the manifold
3/8 in.
valves and remove the vacuum pump.
(10 mm)
4. Connect the refrigerant tank to the center manifold port
of the gauge set. Pressurize the system enough to break
the vacuum.
5. Open both service valves by turning the valve stems ¼
turn counterclockwise. The stem will be in line with the
tubes. Replace the stem caps and tighten. Proceed with
Refrigerant Charging section.
The air conditioning system contains liquid
and gaseous refrigerant under pressure.
Adjustment of refrigerant charge should
only be done by a qualifi ed, EPA certifi ed
technician thoroughly familiar with this type
of equipment.
should the homeowner attempt to install and/
or service this equipment. Failure to comply
with this warning could result in equipment
damage, personal injury, or death.

Refrigerant Charging

NOTE: The unit must be charged at a fi xed speed setting.
For this purpose the thermostat/controller needs to be wired
and powered prior to charging. Using the thermostat, go
to CHARGE MODE under SERVICE TESTS from the
INSTALLER SETTINGS menu, described later in this
document. Select CHARGE MODE to add or verify system
charge. In the CHARGE MODE screen, COOLING mode
must be selected.
WARNING
Under no circumstances
5