![background image](http://html.mh-extra.com/html/carrier/50xz024/50xz024_installation-start-up-and-service-instructions-manual_2563361005.webp)
d. Snap lever down to lock strap in tension buckle. To release
strapping, squeeze safety latch, lift lever, and pull webbing
outward.
5. Tighten the tension buckle until it is taut. Lifting brackets
must be secure in the rigging holds.
6. Attach field-supplied clevis or hook of sufficient strength to
hole in the lifting bracket. (See Fig. 9)
7. Attach the 2 safety straps directly to the clevis or hook at the
4 rigging brackets. DO NOT attach the safety straps to the
lifting brackets. (See Fig. 9)
8. Position lifting point directly over the unit’s center of gravity.
9. Lift unit. When unit is directly over the roof curb, remove the
2 safety straps. Lower the equipment onto the roof curb.
10. After the unit is placed on the roof curb or mounting pad,
remove the top crating. On 50XZ060 units only, 2 wire ties
fastened to the outdoor coils and reversing valve/accumulator
assembly must be cut. Remove the left and front louver panels
and corner post to access wire ties. The wire tie to be cut on
the left is located approximately 4 in. down the tube sheet. The
wire tie to be cut on the right is located approximately 6 in.
down the tube sheet.
Step 5—Select and Install Ductwork
The design and installation of the duct system must be in
accordance with the standards of the NFPA for installation of
non-residence type air conditioning and ventilating systems, NFPA
90A or residence-type, NFPA 90B and/or local codes and ordi-
nances.
Select and size ductwork, supply-air registers, and return air grilles
according to ASHRAE (American Society of Heating, Refrigera-
tion, and Air Conditioning Engineers) recommendations.
The unit has duct flanges on the supply- and return-air openings on
the side of the unit.
When designing and installing ductwork, consider the following:
For vertical supply and return units, tools or parts could drop
into ductwork and cause serious injury or death. Install a 90
degree turn in the return ductwork between the unit and the
conditioned space. If a 90 degree elbow cannot be installed,
then a grille of sufficient strength and density should be
installed to prevent objects from falling into the conditioned
space. Units with electric heaters require 90 degree elbow in
supply duct.
1. All units should have field-supplied filters or accessory filter
rack installed in the return-air side of the unit. Recommended
sizes for filters are shown in Table 1.
2. Avoid abrupt duct size increases and reductions. Abrupt
change in duct size adversely affects air performance.
IMPORTANT:
Use flexible connectors between ductwork and
unit to prevent transmission of vibration. Use suitable gaskets to
ensure weather tight and airtight seal. When electric heat is
installed, use fireproof canvas (or similar heat resistant material)
connector between ductwork and unit discharge connection. If
flexible duct is used, insert a sheet metal sleeve inside duct. Heat
resistant duct connector (or sheet metal sleeve) must extend 24-in.
from electric heater element.
3. Size ductwork for cooling air quantity (cfm). The minimum
air quantity for proper electric heater operation is listed in
Table 2. Heater limit switches may trip at air quantities below
those recommended.
4. Seal, insulate, and weatherproof all external ductwork. Seal,
insulate and cover with a vapor barrier all ductwork passing
through conditioned spaces. Follow latest Sheet Metal and Air
Conditioning Contractors National Association (SMACNA)
and Air Conditioning Contractors Association (ACCA) mini-
mum installation standards for residential heating and air
conditioning systems.
Fig. 4—Corner Weights
CORNER WEIGHTS (SMALL CABINET)
CORNER WEIGHTS (LARGE CABINET)
Model
50XZ
Unit
24
30
36
Model
50XZ
Unit
42
48
60
Total Weight
350
Not
Available
373
Total Weight
Not
Available
463
499
Corner Weight 1
70
“
75
Corner Weight 1
“
98
107
Corner Weight 2
54
“
58
Corner Weight 2
“
61
70
Corner Weight 3
84
“
90
Corner Weight 3
“
127
136
Corner Weight 4
141
“
150
Corner Weight 4
“
177
186
C00071
1
2
4
3
x
y
5