Carrier 48LDT005 - User Manual

Carrier Corporation • Syracuse, N Y 13221
Combination Heating/Cooling Units
INDEX
Page
SAFETY CONSIDERATIONS. 1
INSTALLATION .1-16
Step 1 — Provide Unit Support . 1
• ROOF CURB
• SLAB MOUNT
Step 2 — Field Fabricate Ductwork. 1
Step 3 — Rig and Place Unit. 1
• POSITIONING
Step 4 — Install Flue Hood . 3
Step 5 — Trap Condensate Drain . 3
Step 6 — Install Gas Piping. 3
Step 7 — Make Electrical Connections. 3
• FIELD POWER SUPPLY
• FIELD CONTROL WIRING
• HEAT ANTICIPATOR SETTINGS
Step 8 — Make Outdoor Air Inlet Adjust¬
ments and Install Outdoor Air Hood. 10
• OPTIONAL OUTDOOR AIR DAMPER
• OPTIONAL ECONOMIZER
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INSTALLATION
NOTE: 004,005,006 size units in California require
the installation of an accessory NOx baffle. Refer to
Accessory NOx Baffle Installation Instructions for
details.
Step 1 — Provide Unit Support
ROOF CURB (Downshot Units Only) — Assemble
and install accessory roof curb in accordance with
instructions shipped with curb. Curb details and
information required to field fabricate a roof curb
are shown in Fig. 1. Install insulation, cant strips,
roofing and flashing as shown. Ductwork must be
attached to curb.
Step 9 — Adjust Evaporator Fan Speed. 16
START-UP.16,17
SERVICE.18-22
SAFETY CONSIDERATIONS
Installation and servicing of air conditioning
equipment can be hazardous due to system pressure
and electrical components. Only trained and quali¬
fied service personnel should install, repair or
service air conditioning equipment.
Untrained personnel can perform basic mainte¬
nance functions of cleaning coils and filters and
replacing filters. All other operations should be per¬
formed by trained service personnel. 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.
Curb should be level. Unit leveling tolerance is
1/16 in. per linear foot in any direction. This is
necessary for unit drain to function properly. Refer
to Accessory Roof Curb Installation Instructions
for additional information as required.
SLAB MOUNT(Horizontal Units Only) — Provide
a level concrete slab that extends a minimum of 6 in.
beyond unit cabinet. The slab should be 8 in. thick
with 4 in. above grade. Install a gravel apron in front
of condenser air inlet to prevent grass and foliage
from obstructing airflow. Trap condensate drai.n.
Allow for trap when pouring slab.
Step 2 — Field Fabricate Ductwork — On
downshot units secure all ducts to roof curb and
building structure.
lHiiH Insulate and weatherproof all external duct¬
work, joints and roof openings with flashing and
mastic in accordance with applicable codes.
Ducts passing through an unconditioned space
must be insulated and covered with a vapor barrier.
A minimum clearance is not required around
ductwork. Cabinet return air static shall not exceed
-.35 in. wg with economizer or -.45 in. wg without
economizer.
Step 3 — Rig and Place Unit — Inspect unit for
transportation damage. File any claim with trans¬
portation agency. Keep upright and do not drop.
Carrier Corporation 1984
Form 48H.L-7SI

Carrier 48LDT005 Specifications

General

Model	48LDT005
Type	Air Handler
Cooling Capacity	5 tons
Airflow	2000 CFM
Voltage	208/230V
Phase	1
Refrigerant	R-410A
Motor Type	PSC
Cabinet Construction	Galvanized Steel
Filter Type	Disposable

Summary

SAFETY CONSIDERATIONS

INSTALLATION

Provide Unit Support

Instructions for assembling and installing roof curb or concrete slab support for the unit.

Field Fabricate Ductwork

Guidelines for insulating and weatherproofing external ductwork and ensuring proper airflow.

Rig and Place Unit

Procedures for inspecting, rigging, and positioning the unit, ensuring proper clearances.

Install Flue Hood

Trap Condensate Drain

Install Gas Piping

Make Electrical Connections

Procedures for field power supply and control wiring, including voltage considerations.

Make Outdoor Air Inlet Adjustments and Install Outdoor Air Hood

Steps for adjusting the outdoor air damper and installing the air hood assembly.

Adjust Evaporator Fan Speed

START-UP

Cooling

Heating

Economizer Operating Sequence

Explains how the economizer operates in cooling mode based on ambient temperature.

HEATING MODE

Describes the outdoor air damper behavior during heating mode and unoccupied periods.

SERVICE

Cleaning

Condenser Coil

Condensate Drain

Condenser Air Fan Adjustment

Refrigerant Charge

Procedures for checking and adjusting the refrigerant charge using specific charts.

Low Charge Cooling

Detailed method for charging the unit for cooling using specialized charging charts.

Main and Pilot Burners

Inspection and adjustment of main and pilot burners for proper flame appearance.

Flue Gas Passageways

Combustion Air Blower

Automatic Pilot Adjustment

Main Burners