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8
INSPECTION
Prior to initial use, and at monthly intervals, all rigging brackets and
straps should be visually inspected for any damage, evidence of
wear, structural deformation, or cracks. Particular attention should
be paid to excessive wear at hoist hooking points and load support
areas. Brackets or straps showing any kind of wear in these areas
must not be used and should be discarded.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installing or servicing system, always turn off main
power to system. There may be more than one disconnect
switch. Turn off accessory heater power switch if applicable.
Tag disconnect switch with a suitable warning label.
!
WARNING
UNIT FALLING HAZARD
Failure to follow this warning could result in personal injury
or death.
Never stand beneath rigged units or lift over people.
!
WARNING
INTRODUCTION
The lifting/rigging bracket is engineered and designed to be
installed only on Small Packaged Products.
This bracket is to be used to rig/lift a Small Packaged Product onto
roofs or other elevated structures.
PROPERTY DAMAGE HAZARD
Failure to follow this warning could result in personal
injury/death or property damage.
Rigging brackets for one unit use only.
When removing a
unit at the end of its useful life, use a new set of brackets.
!
WARNING
USE OF RIGGING BRACKET
Field Installation of Rigging Bracket
1. If applicable, remove unit from shipping carton. Leave top
shipping skid on the unit for use as a spreader bar to prevent
the rigging straps from damaging the unit. If the skid is not
available, use a spreader bar of sufficient length to protect the
unit from damage.
2. Remove 4 screws in unit corner posts.
3. Attach each of the 4 metal rigging brackets under the panel
rain lip (See Fig. 7). Use the screws removed in step 2 above
to secure the brackets to the unit.
PROPERTY DAMAGE HAZARD
Failure to follow this warning could result in personal
injury/death or property damage.
Rigging bracket MUST be under the rain lip to provide
adequate lifting.
!
WARNING
PROPERTY DAMAGE HAZARD
Failure to follow this warning could result in personal
injury/death or property damage.
Do not strip screws when re--securing the unit. If a screw is
stripped, replace the stripped one with a larger diameter screw
(included).
!
WARNING
Rigging/Lifting of Unit
1. Bend top of brackets down approximately 30 degrees from
the corner posts.
2. Attach straps of equal length to the rigging brackets at
opposite ends of the unit. Be sure straps are rated to hold the
weight of the unit (See Fig. 7).
3. Attach a clevis of sufficient strength in the middle of the
straps. Adjust the clevis location to ensure unit is lifted level
with the ground.
4. After unit is securely in place detach rigging straps. Remove
corner posts, screws, and rigging brackets then reinstall
screws.
UNIT FALLING HAZARD
Failure to follow this warning could result in personal
injury/death or property damage.
When straps are taut, the clevis should be a minimum of 36
inches above the unit top cover.
!
WARNING
After the unit is placed on the roof curb or mounting pad, remove
the top crating.
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 ordinances.
Select and size ductwork, supply--air registers, and return air grilles
according to ASHRAE (American Society of Heating,
Refrigeration, and Air Conditioning Engineers) recommendations.
The unit has duct flanges on the supply-- and return--air openings on
the side of the unit.
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
For vertical supply and return units, tools or parts could drop
into ductwork, therefore, 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.
!
WARNING
When designing and installing ductwork, consider the following:
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.
48D
U