Table of Contents
Advertisement
UN-CRATE UNIT
Remove unit packaging except for the top skid assembly, which
should be left in place until after the unit is rigged into its final
location.
INSPECT SHIPMENT
File a claim with shipping company if the shipment is damaged or
incomplete.
CONSIDER SYSTEM REQUIREMENTS
Consult local building codes and National Electrical Code (NEC,
U.S.A.) for special installation requirements.
Allow sufficient space for airflow clearance, wiring, refrigerant
piping, and servicing unit. See Fig. 3 for unit dimensions and
Table 4 for weight distribution data.
Locate the unit so that the outdoor coil (condenser) airflow is un-
restricted on all sides and above.
The unit may be mounted on a level pad directly on the base chan-
nels or mounted on raised pads at support points. See Table 4 for
weight distribution based on recommended support points.
NOTE: If vibration isolators are required for a particular installa-
tion, use the data in Table 4 to make the proper selection.
Step 3 — Prepare Unit Mounting Support
SLAB MOUNT
Provide a level concrete slab that extends a minimum of 6 in.
(150 mm) beyond unit cabinet. Install a gravel apron in front of
condenser coil air inlet to prevent grass and foliage from obstruct-
ing airflow.
Rig and Mount the Unit
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
All panels must be in place when rigging. Unit is not designed
for handling by fork truck when packaging is removed.
If using top crate as spreader bar, once unit is set, carefully
lower wooden crate off building roof top to ground. Ensure
that no people or obstructions are below prior to lowering the
crate.
RIGGING
These units are designed for overhead rigging. Refer to the rigging
label for preferred rigging method. Spreader bars are not required
if top crating is left on the unit. All panels must be in place when
rigging. As further protection for coil faces, plywood sheets may
be placed against the sides of the unit, behind cables. Run cables
to a central suspension point so that the angle from the horizontal
is not less than 45 degrees. Raise and set the unit down carefully.
If it is necessary to roll the unit into position, mount the unit on
longitudinal rails, using a minimum of 3 rollers. Apply force to the
rails, not the unit. If the unit is to be skidded into position, place it
on a large pad and drag it by the pad. Do not apply any force to the
unit.
Raise from above to lift the unit from the rails or pad when unit is
in its final position.
After the unit is in position, remove all shipping materials and top
crating.
Step 4 — Determine Refrigerant Line Sizes
Select the recommended line sizes for 38AUZ and 38AUD unit
from the appropriate tables.
Determine the linear length of interconnecting piping required
between the outdoor unit and indoor unit (evaporator). Consider
and identify also the arrangement of the tubing path (quantity
and type of elbows in both lines), liquid line solenoid size, filter
drier and any other refrigeration specialties located in the liquid
line. Refer to the indoor unit installation instructions for addi-
tional details on refrigeration specialties devices.
Determine equivalent line length adjustments for path and compo-
nents and add to linear line lengths. See Table 7, Equivalent
Lengths for Common Fittings, for usual fitting types. Also identify
adjustments for refrigeration specialties. Refer to Part 3 of the
Carrier System Design Manual for additional data and information
on equivalent lengths.
Table 7 — Equivalent Lengths for Common Fittings (ft)
NOMINAL
TUBE OD
90° Std
90° Lrad 90° Street
(in.)
3/8
1.3
1/2
1.4
5/8
1.6
3/4
1.8
7/8
2.0
1-1/8
2.6
1-3/8
3.3
1-5/8
4.0
NOMINAL
TUBE OD
Branch
(in.)
Flow
3/8
2.6
1/2
2.7
5/8
3.0
3/4
3.5
7/8
4.0
1-1/8
5.0
1-3/8
7.0
1-5/8
8.0
2-1/8
10.0
NOTE: Equivalent line lengths will vary based on tube diameter.
Calculate equivalent line length for each pipe by adding equiva-
lent length adjustments to linear lengths for each pipe.
Enter the appropriate table to select the recommended line sizes.
MODEL NUMBER
POSITION #6
38AUZ
38AUD
LIQUID LIFT
A liquid lift condition exists when the outdoor unit is located be-
low the indoor (evaporator) unit and liquid flows vertically up in a
portion of the liquid line. The vertical column of liquid reduces the
available state point sub-cooling at the evaporator coil's thermal
expansion valve. This effect reduces the length of liquid lift (feet
of elevation) that a liquid line size can accommodate. Longer lin-
ear tube lengths will also reduce the amount of liquid lift possible.
Check Tables 8 (38AUZ) and 9 (38AUD) for maximum liquid lift
capabilities for line sizes. Reselect the liquid line tube size if nec-
essary. If maximum available tube size cannot provide the re-
quired lift distance on this installation, relocate the outdoor unit to
reduce the equivalent line length or the lift requirement.
7
ELBOWS
90° Std
0.8
2.2
0.6
0.9
2.3
0.7
1.0
2.5
0.8
1.2
2.9
0.9
1.4
3.2
0.9
1.7
4.1
1.3
2.3
5.6
1.7
2.6
6.3
2.1
TEES
Straight-Thru
Reduce
No Reduct
25%
0.8
1.1
0.9
1.2
1.0
1.4
1.2
1.7
1.4
1.9
1.7
2.3
2.3
3.1
2.6
3.7
3.3
4.7
QUANTITY OF
TABLE
LINE SETS
8
1
9
2
90° Street
1.0
1.1
1.3
1.5
1.6
2.1
3.0
3.4
Reduce
50%
1.3
1.4
1.6
1.8
2.0
2.6
3.3
4.0
5.0
Advertisement
Table of Contents
