Carrier 48TJD - User Manual

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111 Catalog No. 534-774 Printed in U.S.A. Form 48TJ-18SI Pg 1 10-00 Replaces: 48TJ-16SI
Book 1 4
Ta b 1 a 6 a
Installation, Start-Up and
Service Instructions
CONTENTS
Page
SAFETY CONSIDERATIONS
. . . . . . . . . . . . . . . . . . . . . . 1
INSTALLATION
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-36
Step 1 — Provide Unit Support
. . . . . . . . . . . . . . . . . . . 1
•ROOF CURB
• SLAB MOUNT
Step 2 — Field Fabricate Ductwork
. . . . . . . . . . . . . . . 2
Step 3 — Install External Trap for
Condensate Drain
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Step 4 — Rig and Place Unit
. . . . . . . . . . . . . . . . . . . . . 2
• POSITIONING
Step 5 — Install Flue Hood
. . . . . . . . . . . . . . . . . . . . . . . 4
Step 6 — Install Gas Piping
. . . . . . . . . . . . . . . . . . . . . . 4
Step 7 — Make Electrical Connections
. . . . . . . . . . . 5
• DISCONNECT BOX LOCATION
• FIELD POWER SUPPLY
• FIELD CONTROL WIRING
• HEAT ANTICIPATOR SETTINGS
Step 8 — Make Outdoor-Air Adjustment and
Install Outdoor-Air Hood
. . . . . . . . . . . . . . . . . . . . . . 12
• MANUAL OUTDOOR-AIR DAMPER
• OPTIONAL DURABLADE ECONOMIZER
• OPTIONAL ECONOMI$ER
Step 9 — Adjust Evaporator-Fan Speed
. . . . . . . . . 20
• DIRECT-DRIVE MOTORS
• BELT-DRIVE MOTORS
START-UP
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37-39
SERVICE
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40-44
TROUBLESHOOTING
. . . . . . . . . . . . . . . . . . . . . . . . . 45-50
START-UP CHECKLIST
. . . . . . . . . . . . . . . . . . . . . . . . CL-1
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
install, repair, or service air-conditioning equipment.
Untrained personnel can perform basic maintenance func-
tions of cleaning coils and filters and replacing filters. All other
operations should be performed by trained service personnel.
When working on air-conditioning equipment, observe precau-
tions in the literature, tags and labels attached to the unit, and
other safety precautions that 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
Unit is shipped in the vertical discharge configuration. To
convert to horizontal configuration, remove screws from side
duct opening covers and remove covers. Using the same
screws, install covers on vertical duct openings with the insula-
tion side down. Seals around duct openings must be tight. See
Fig. 1.
Step 1 — Provide Unit Support
ROOF CURB — Assemble and install accessory roof curb in
accordance with instructions shipped with curb. See Fig. 2. In-
stall insulation, cant strips, roofing felt, and counter flashing as
shown.
Ductwork must be attached to curb, not to the unit. The
accessory thru-the-bottom power and gas connection package
must be installed before the unit is set on the roof curb.
If field-
installed (thru-the-roof curb) gas connections are desired, use
factory-supplied
3
/
4
in. pipe coupling and gas plate assembly to
mount the thru-the-roof curb connection to the roof curb. Gas
connections and power connections to the unit must be field in-
stalled after the unit is installed on the roof curb.
If electric and control wiring is to be routed through the
basepan, attach the accessory thru-the-bottom service connec-
tions to the basepan in accordance with the accessory installa-
tion instructions.
Ensure voltage listed on unit data plate agrees with electri-
cal supply provided for the unit.
Disconnect gas piping from unit when leak
testing at pressure greater than
1
/
2
psig. Pres-
sures greater than
1
/
2
psig will cause gas valve
damage resulting in hazardous condition. If
gas valve is subjected to pressure greater than
1
/
2
psig, it
must
be replaced before use. When
pressure testing field-supplied gas piping at
pressures of
1
/
2
psig or less, a unit connected to
such piping must be isolated by manually clos-
ing the gas valve.
Before performing service or maintenance operations on
unit, turn off main power switch to unit and install lockout
tag. Electrical shock could cause personal injury.
IMPORTANT: The gasketing of the unit to the roof curb
is critical for a watertight seal. Install gasket supplied
with the roof curb as shown in Fig. 2. Improperly
applied gasket can also result in air or water leaks and
poor unit performance.
48TJE,TJF004
48TJD,TJE,TJF005-007
Single-Package Rooftop Heating/Cooling Units

Summary

Safety Considerations

Installation

Provide Unit Support

Assemble and install accessory roof curb in accordance with instructions shipped with curb.

Field Fabricate Ductwork

Secure all ducts to roof curb and building structure on vertical units.

Install External Trap for Condensate Drain

Install a trap at least 4-in. deep and protect against freeze-up.

Rig and Place Unit

Inspect unit for transportation damage and keep unit upright.

Install Flue Hood

Flue hood is shipped screwed to the burner compartment access panel.

Install Gas Piping

Unit is equipped for use with type of gas shown on nameplate.

Make Electrical Connections

Unit cabinet must have an uninterrupted, unbroken electrical ground.

Make Outdoor-Air Adjustments and Install Outdoor-Air Hood

Details how to adjust outdoor-air damper and install the outdoor-air hood.

Adjust Evaporator-Fan Speed

Adjust evaporator-fan rpm to meet jobsite conditions.

Optional Durablade Economizer

Economizer Assembly

Determine ventilation air requirements and prepare the unit for installation.

Optional Economiser

Economiser Assembly

Remove the EconoMi$er hood from its packaging and assemble.

Start-Up

Unit Preparation

Ensure unit is installed according to instructions and applicable codes.

Heating Operation

Adjust Gas Input

Procedure to measure and adjust gas input for natural gas and propane.

Operating Sequence

Cooling, Units Without Economizer

Unit operation sequence when cooling without an economizer.

Heating, Units Without Economizer

Unit operation sequence when heating without an economizer.

Cooling, Units With Durablade Economizer

Operation sequence for cooling with a Durablade Economizer.

Cooling, Units With Economiser

Operation sequence for cooling with an Economiser.

Heating, Units With Economiser

Operation sequence for heating with an Economiser.

Service Procedures

Evaporator Coil Cleaning

Instructions for cleaning the evaporator coil.

Condenser Coil Cleaning

Instructions for cleaning the condenser coil.

Refrigerant Charge

Low-Charge Cooling

Using cooling charging charts to adjust refrigerant.

Burner Ignition System

Main Burners

Access, inspect, and adjust main burners.

Gas Train Removal and Replacement

Step-by-step instructions for removing and replacing the gas train.

Troubleshooting Guide

LED Error Code Service Analysis

Explains LED error codes and their corresponding remedies.

Heating Service Analysis

Troubleshooting common heating problems and their causes/remedies.

Cooling Service Analysis

Troubleshooting common cooling problems and their causes/remedies.

Durablade Economizer Troubleshooting

EconoMi$er Troubleshooting

Wiring Diagram Legend

Start-Up Checklist

Carrier 48TJD Specifications

General

Model Number	48TJD
Category	Air Conditioner
Energy Efficiency Ratio (EER)	11.0
Voltage	208/230V or 460V
Compressor Type	Scroll
Refrigerant	R-410A
Cooling Capacity	24, 000-60, 000 BTU/h
Phase	Three
Weight (Outdoor Unit)	Varies by capacity
Type	Packaged Rooftop Unit