Carrier 48AJ/AK/AMD020, Installation Instructions Manual

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Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111 Catalog No. 535-00075 Printed in U.S.A. Form 50A-1SI Pg 1 7-03 Replaces: New
Book 1
Tab 1b
Installation Instructions
CONTENTS
Page
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . 1
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-46
Step 1 — Provide Unit Support . . . . . . . . . . . . . . . . . . . 1
• ROOF CURB
• ALTERNATE UNIT SUPPORT
Step 2 — Rig and Place Unit . . . . . . . . . . . . . . . . . . . . . 1
• POSITIONING
• ROOF MOUNT
Step 3 — Field Fabricate Ductwork . . . . . . . . . . . . . . . 2
Step 4 — Make Unit Duct Connections
. . . . . . . . . . . 2
Step 5 — Trap Condensate Drain . . . . . . . . . . . . . . . . 18
Step 6 — Make Electrical Connections . . . . . . . . . . 18
• POWER WIRING
• FIELD POWER SUPPLY
• FIELD CONTROL WIRING
Step 7 — Make Outdoor-Air Inlet
Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
• ECONOMIZER AND FIXED OUTDOOR
AIR DAMPER
Step 8 — Position Power Exhaust/Barometric
Relief Damper Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Step 9 — Route Static Pressure Sensors
. . . . . . . . 45
Step 10 — Install All Accessories . . . . . . . . . . . . . . . 45
Step 11 — Field Modifications . . . . . . . . . . . . . . . . . . . 46
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment can
be hazardous due to system pressure and electrical compo-
nents. Only trained and qualified service personnel should in-
stall, repair, or service air-conditioning equipment.
Untrained personnel can perform the basic maintenance
functions of cleaning coils and filters and replacing filters. All
other operations should be performed by trained service per-
sonnel. When working on air-conditioning equipment, observe
precautions in the literature, tags and labels attached to the unit,
and other safety precautions that may apply.
Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloth for unbrazing operations. Have
fire extinguishers available for all brazing operations.
INSTALLATION
Step 1 — Provide Unit Support
ROOF CURB — For vertical discharge units, assemble or in-
stall accessory roof curb in accordance with instructions
shipped with this accessory. See Fig. 1-4. Install insulation,
cant strips, roofing, and counter flashing as shown. Ductwork
can be installed to roof curb before unit is set in place. Curb
should be level. This is necessary to permit unit drain to func-
tion properly. Unit leveling tolerance is shown in Fig. 1-4.
Refer to Accessory Roof Curb Installation Instructions for
additional information as required. When accessory roof curb
is used, unit may be installed on class A, B, or C roof covering
material.
ALTERNATE UNIT SUPPORT — When the preferred curb
or slab mount cannot be used, support unit with sleepers on
perimeter, using unit curb support area. If sleepers cannot be
used, support long sides of unit (refer to Fig. 5-10) with a mini-
mum number of 4-in. x 4-in. pads spaced as follows:
50AJ,AK,AW,AY020-035 units require 3 pads on each side;
50AJ,AK,AW,AY040-050 units require 4 pads on each side;
50AJ,AK,AW,AY060 units require 6 pads on each side. Unit
may sag if supported by corners only.
Step 2 — Rig and Place Unit —
Inspect unit for
transportation damage. See Tables 1-3 for physical data and
specifications. File any claim with transportation agency.
Do not drop unit; keep upright. Use spreader bars over unit
to prevent sling or cable damage. This unit must be handled
with a crane and can not be handled by a fork truck. Level by
using unit frame as a reference; leveling tolerance is shown in
Fig. 1-4. See Fig. 11 for additional information. Unit operating
weight is shown in Table 2.
Before performing service or maintenance operations on
unit, turn off main power switch to unit. Electrical shock
could cause personal injury.
1. Improper installation, adjustment, alteration, service,
or maintenance can cause property damage, personal
injury, or loss of life. Refer to the User’s Information
Manual provided with this unit for more details.
2. Do not store or use gasoline or other flammable va-
pors and liquids in the vicinity of this or any other
appliance.
1. All panels must be in place when rigging.
2. Unit is not designed for handling by fork truck.
IMPORTANT: The gasketing of the unit to the roof curb is
critical for a watertight seal. Install gasket with the roof
curb as shown in Fig. 1-4. Improperly applied gasket can
also result in air leaks and poor unit performance.
50AJ,AK,AW,AY020-060
With Scroll Compressor and
Comfort Link™ Control
Single Package Rooftop Units
Electric Cooling with Electric Heat Option