AAON V3-E - Manual (Page 27)

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Only clean ACR tubing should be used.
Piping should conform to generally accepted
practices and codes.
The air handling unit coils are pressurized.
The copper caps must be punctured to
permit a gradual escape of the pressure prior
to un-sweating those caps. Immediately
couple the tubing to the indoor unit to avoid exposing the coils to moisture. A properly
sized filter drier is furnished in the
condenser.
When making solder
connections, make sure dry nitrogen flows
through the lines, when heating the copper,
to prevent oxidization inside of the copper.
When
piping is completed
interconnecting piping and air handling
unit must be evacuated to 500 microns or
less and leak checked. Condenser shutoff
valves can then be opened to allow
refrigerant to flow to the air handling unit.
Thermal expansion valve bulbs should be
mounted with good thermal contact on a
horizontal section of the suction line close to
the evaporator, but outside the cabinet, and
well insulated.
Figure 9 - TXV Bulb Position
Refrigerant lines should be fastened and
supported according to local codes.
Unit
should be charged based on
determination of sub-cooling and superheat.
See Adjusting Refrigerant Charge section
for more information.
Refrigerant reheat coil for the modulating
hot gas reheat option is factory installed.
Liquid line receiver should be installed at
the condensing unit. Care must be taken not
to cross circuits in reheat systems.
Piping shall be in accordance with
national and local codes. Pressure
limiting devices, backflow preventers
and all other safety requirements are
the sole responsibility of the installing
contractor.
WARNING
Improper installation, adjustment,
alteration, service or maintenance
can
cause property damage,
personal injury or loss of life. Startup
and service must be performed by a
Factory Trained Service Technician.
A copy of this IOM should be kept
with the unit.
WARNING
This section is for information only
and is not intended to provide all
details required by the designer or
installer of the refrigerant piping
between
the condenser or
condensing unit and the air handling
unit. AAON is not responsible for
interconnecting
refrigerant piping.
Consult ASHRAE Handbook
–
Refrigeration and ASME Standards.
CAUTION