AAON CA-25 - Manual (Page 3)

3
INSTALLATION
AAON Coil Products 'CA' Series units are designed for fast easy installation
GENERAL
All CA condensing units have lifting areas at the under-
side of the equipment to allow moving and placement
without physical damage. Arrange spreader bars,
blocking or other lifting devices to prevent any dam-
age to the coils or cabinet of the condensing unit.
These condensing units may be placed on a roof or at
ground level since they are designed for exposure to
weather.
When roof mounted, a steel frame must be provided
that will support the unit above the roof itself.
When installed at ground level, a substantial base must
be provided that will not settle.
LOCATION
Airflow to and from the condensing unit must not be
restricted. Obstruction to air flow will result in de-
creased performance and efficiency. The installation
position must provide at least 3 feet of side clearance
for proper air flow into the coils. When units are
mounted adjacent to each other the clearance re-
quired between them would be 6 feet.
Condensing units should not be installed in an enclo-
sure or pit that is deeper than the height of the unit.
When a recessed installation is used the side clear-
ance requirement is doubled to 6 feet for the inlet air.
The CA 02 through CA 05 model sizes have a horizontal
airflow pattern. The discharge air side of one unit
should not be aligned with the intake of another. The
discharge air should be faced away from the adja-
cent building or structure.
The CA 08 through CA 25 models have a vertical air
discharge. There must be no obstruction above the
equipment that may deflect this air back to the inlet of
the condensing unit. Do not place the unit under an
overhang.
Condensing unit operation can also be affected by
wind. It is good practice to position the unit so its length
is parallel with the prevailing wind.
SERVICE CLEARANCE
One end of the CA condensing unit contains the
access door that must be accessible for periodic
service. This area contains the compressor, controls,
safety devices, refrigerant service and shut-off valves.
▲
! WARNING
Electric shock hazard. Can cause injury or death.
Before attempting to perform any service or
maintenance, turn the electrical power to unit to
OFF at disconnect switch(es). Unit may have
multiple power supplies.
It is recommended that a minimum of 4 feet be left free
at this end of the unit for proper and easier servicing.
SETTING THE UNIT
If cables or chains are used to hoist the unit, care
should be taken to prevent damage to the cabinet.
Hoist unit to a point directly above the pad, and lower
unit into the proper place. Unit may also be positioned
with a forktruck. Remove the harness used in hoisting.
Make sure the unit is properly seated and level.
ELECTRICAL
Check the unit data plate to make sure it agrees with
the power supply. Connect power to the unit accord-
ing to the wiring diagram provided with the unit.
The power and control wiring may be brought in
through the holes provided at one corner of the unit.
Protect the branch circuit in accordance with code
requirements. If the control wires are to run inside the
same conduit, use 600 volt wire or as required by
applicable codes. The unit must be electrically
grounded in accordance with the National Electric
Code, ANSI / NFPA No. 70-1984 when installed if an
external source is utilized, in Canada use current C.S.A.
Standard C22.1 Canadian Electric Code Part 1.
Power wiring is to the unit terminal block or compressor
contactor. All wiring beyond this point has been done
by the manufacturer.
Connect the control wiring and apply power to the unit.
CHECK COMPRESSOR FOR PROPER ROTATION BY START-
ING UNIT ONLY AFTER CONNECTING PRESSURE GAUGES
TO SUCTION AND DISCHARGE.
THE COMPRESSOR WILL BE DESTROYED IF RUN IN THE
WRONG DIRECTION.
NOTE: All units are factory wired for 230, 380, 415, 460
or 575 volt.
THERMOSTAT
Low voltage room thermostat should be located on an
inside wall 4 to 5 feet above the floor where it will not
be subjected to drafts, sun exposure or heat from
electrical fixtures or appliances. Follow manufacturer's
instructions enclosed with thermostat for general in-
stallation procedure.
▲
! IMPORTANT
Three phase Scroll Compressors are directional
and start-up must be performed by a qualified
service technician using suction and discharge
gauges.