Carrier 48LD008 - 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 48LD008 Specifications

General

Brand	Carrier
Model	48LD008
Category	Air Handlers
Language	English

Summary

SAFETY CONSIDERATIONS

General Safety Precautions

Essential safety guidelines to follow before and during service operations.

Electrical and Gas Safety

Critical warnings regarding electrical shock and gas hazards during installation.

INSTALLATION

Unit Support and Rigging Procedures

Instructions for supporting, rigging, and positioning the unit on site.

Ductwork and Gas Piping Installation

Steps for fabricating ductwork and connecting the gas piping.

Electrical Connections and Wiring

Detailed steps for making field power and control wiring connections.

Outdoor Air Inlet Adjustments and Hood Installation

Adjusting outdoor air inlets, installing the hood and damper.

Evaporator Fan Speed Adjustment

Methods to adjust the evaporator fan speed for optimal performance.

START-UP

Unit Preparation and System Checks

Ensuring the unit is ready for operation by checking filters and wiring.

Cooling Start-Up and Operation

Steps for initiating and verifying cooling mode operation.

Heating Start-Up and Operation

Procedures for initiating and verifying heating mode operation.

Economizer Operating Sequence

Understanding economizer behavior in cooling and heating modes.

SERVICE

Coil Cleaning and Maintenance

Procedures for cleaning evaporator and condenser coils.

Refrigerant Charge Adjustment Procedures

Methods and charts for correctly adjusting system refrigerant charge.

Burner and Combustion System Service

Maintenance and adjustment of burners, pilot, and combustion air blower.

Component Removal and Replacement

Guidance on removing and replacing major unit components.