5
NDS OUTDOOR SPLIT INSTALLATION MANUAL
Installing and servicing heating and air conditioning
equipment can be hazardous due to system pressure and
electrical components. Only trained and qualified service
personnel should install, repair or service heating and air
conditioning equipment. Untrained personnel can perform
the basic maintenance functions of cleaning coils and
cleaning and replacing filters. All other operations should
be performed by trained service personnel. When working
on heating and air conditioning equipment, observe
precautions in the literature, tags and labels attached to the
unit and other safety precautions that may apply, such as
the following safety measures:
• Follow all safety codes.
• Wear safety glasses and work gloves.
• Use a quenching cloth for brazing operations.
• Have a fire extinguisher available for all brazing
operations.
Moving and Storage
Move units in the normal “up” orientation. Units may be
moved and stored per the information on the packaging.
Do not stack more than three units in total height. Do not
attempt to move units while stacked. When the equipment
is received, all items should be carefully checked against
the bill of lading to be sure all crates and cartons have been
received. Examine units for shipping damage, removing
the units from the packaging if necessary. Units in question
should also be internally inspected. If any damage is noted,
the carrier should make the proper notation on the delivery
receipt, acknowledging the damage.
Split Unit Location
Locate the split compressor section away from areas that
may disturb the customer and in a way that allows easy
removal of the access panels and the top of the cabinet.
Provide sufficient room to make water, electrical and
refrigerant line connections and allow space for service
personnel to perform maintenance. The NDS split is
approved for outdoor installation when properly installed.
Air Coil Location
Refer to the air handler manufacturer’s instructions for the
blower coil unit for details on installing the air handling
portion of the system.
WARNING: Before performing service or
maintenance operations on a system, turn off main
power switches to both units. Turn off accessory
heater power switch if applicable. Electrical
shock could cause personal injury. Installing and
servicing heating and air conditioning equipment
can be hazardous due to system pressure and
electrical components. Only trained and qualified
service personnel should install, repair or service
heating and air conditioning equipment.
Condensate Drain
Follow the blower coil manufacturer’s instructions.
Duct System
All blower coil units/air coils must be installed as specified
by the manufacturer’s installation instructions; however, the
following recommendations should considered to minimize
noise and service problems.
An air filter must always be installed upstream of the air coil
on the return air side of the air handler or furnace. If there
is limited access to the filter rack for normal maintenance, it
is suggested that a return air filter grill be installed. Be sure
that the return duct is properly installed and free of leaks
to prevent dirt and debris from bypassing the filter and
plugging the air coil.
In applications using galvanized metal ductwork, a flexible
duct connector is recommended on both the supply and
return air plenums to minimize vibration from the blower. To
maximize sound attenuation of the unit blower, the supply
and return plenums should include an internal duct liner
of 1-inch thick glass fiber or be constructed of ductboard.
Insulation is usually not installed in the supply branch
ducts. Ducts in unconditioned areas should be wrapped
with a minimum of 1-inch duct insulation. Application of
the unit to uninsulated ductwork in an unconditioned
space is not recommended as the unit’s performance will
be adversely affected. If the air handler is connected to
existing ductwork, a previous check should have been
made to assure that the duct system has the capacity to
handle the air required for the unit application. If ducting
is too small, as in replacement of heating only systems,
larger ductwork should be installed. All existing ductwork
should be checked for leaks and repairs made accordingly.
The duct systems and diffusers should be sized to handle
the design airflow quietly. If air noise or excessive airflow
is a problem, the blower speed can be changed to a lower
speed to reduce airflow. This will reduce the performance
of the unit slightly in heating; however, it will increase the
temperature rise across the air coil. Airflow must still meet
minimum requirements.
Equipment Selection
The following guidelines should be used when mating an
Envision Split to an air handler/coil.
• Select R-410A components only.
• Match the air handler to the air handler coil data table.
• Indoor matching adjustable TXV is factory installed on
every NAH air handler/coil. Fixed orifice or cap tube
systems should not be used.
• Minimum of two (2) blower speeds
Utilizing Existing Coil or Air Handler
It is recommended that a new R-410A air handler be
installed with an Envision Split considering the long term
Safety Considerations
General Installation Information
