Carrier 48EZ(N)-A - Manual (Page 2)

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es which may result in minor personal injury or product and prop-
erty damage. NOTE is used to highlight suggestions which will
result in enhanced installation, reliability, or operation.
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 and install lockout tag. There may be
more than one disconnect switch. Turn off accessory heater
power switch if applicable.
! WARNING
FIRE, EXPLOSION, ELECTRICAL SHOCK AND
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury, death or property damage.
A qualified installer or agency must use only
factory--authorized kits or accessories when modifying this
product.
WARNING
!
CUT HAZARD
Failure to follow this caution may result in personal injury.
When removing access panels (see Fig. 18) or performing
maintenance functions inside your unit, be aware of sharp
sheet metal parts and screws. Although special care is taken
to reduce sharp edges to a minimum, be extremely careful
when handling parts or reaching into the unit.
CAUTION
!
INTRODUCTION
The 48EZ--A unit (see Fig. 1) is a fully self--contained,
combination Category I gas heating/electric heating and cooling
unit designed for outdoor installation (See Fig. 2 and 3 for unit
dimensions). All unit sizes have return and discharge openings for
both horizontal and downflow configurations, and are factory
shipped with all downflow duct openings covered. Units may be
installed either on a rooftop, or on a cement slab (See Fig. 4 for
roof curb dimensions).
In gas heating mode, this unit is designed for a minimum
continuous return--air temperature of 55_F (13_C) db and a
maximum continuous return--air temperature of 80_F (27_C) db.
Failure to follow these return--air temperature limits may affect
reliability of heat exchangers, motors, and other components.
Models with an N in the fifth position of the model number are
dedicated Low NOx units designed for California installations.
These models meet the California maximum oxides of nitrogen
(NOx) emissions requirements of 40 nanograms/joule or less as
shipped from the factory and must be installed in California Air
Quality Management Districts or any other regions in North
America where a Low NOx rule exists.
RECEIVING AND INSTALLATION
Step 1 — Check Equipment
IDENTIFY UNIT
The unit model number and serial number are stamped on the unit
information plate. Check this information against shipping papers.
INSPECT SHIPMENT
Inspect for shipping damage before removing packaging materials.
If unit appears to be damaged or is torn loose from its anchorage,
have it examined by transportation inspectors before removal.
Forward claim papers directly to transportation company.
Manufacturer is not responsible for any damage incurred in transit.
Check all items against shipping list. Immediately notify the
nearest equipment distribution office if any item is missing. To
prevent loss or damage, leave all parts in original packages until
installation.
If the unit is to be mounted on a curb in a downflow application,
review Step 9 to determine which method is to be used to remove
the downflow panels before rigging and lifting into place. The
panel removal process may require the unit to be on the ground.
Step 2 — Provide Unit Support
For hurricane tie downs, contact distributor for details and PE
(Professional Engineering) Certificate if required.
ROOF CURB
Install accessory roof curb in accordance with instructions shipped
with curb (See Fig. 4). Install insulation, cant strips, roofing, and
flashing. Ductwork must be attached to curb.
IMPORTANT: The gasketing of the unit to the roof curb is
critical for a water tight seal. Install gasketing material supplied
with the roof curb. Improperly applied gasketing also can result in
air leaks and poor unit performance.
Curb should be level to within 1/4 in. (6 mm). This is necessary for
unit drain to function properly. Refer to accessory roof curb
installation instructions for additional information as required.
Installation on older “G” series roof curbs.
Two accessory kits are available to aid in installing a new “G”
series unit on an old “G” roof curb.
1. Accessory kit number CPADCURB001A00, (small chassis)
and accessory kit number CPADCURB002A00, (large
chassis) includes roof curb adapter and gaskets for the
perimeter seal and duct openings. No additional
modifications to the curb are required when using this kit.
2. An alternative to the adapter curb is to modify the existing
curb by removing the outer horizontal flange and use
accessory kit number CPGSKTKIT001A00 which includes
spacer blocks (for easy alignment to existing curb) and
gaskets for the perimeter seal and duct openings. This kit is
used when existing curb is modified by removing outer
horizontal flange.
UNIT/STRUCTURAL DAMAGE HAZARD
Failure to follow this caution may
result in property
damage.
Ensure there is sufficient clearance for saw blade when
cutting the outer horizontal flange of the roof curb so there
is no damage to the roof or flashing.
CAUTION
!
SLAB MOUNT
Place the unit on a solid, level concrete pad that is a minimum of 4
in. (102 mm) thick with 2 in. (51 mm) above grade. The slab
should be flush on the compressor end of the unit (to allow
condensate drain installation) and should extend 2 in. (51 mm) on
the three remaining sides of the unit. Do not secure the unit to the
slab except when required by local codes.
Ducts passing through an unconditioned space must be insulated
and covered with a vapor barrier.
48E
Z
--
A