Carrier 48LC 05, Service And Maintenance Instructions

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48LC*04---06
Nominal 3 to 5 Tons
Single Package Rooftop
Gas Heating/Electric Cooling Unit
with Puron
r
(R---410A) Refrigerant
Service and Maintenance Instructions
TABLE OF CONTENTS
SAFETY CONSIDERATIONS 1 . . . . . . . . . . . . . . . . . . . .
UNIT ARRANGEMENT AND ACCESS 2 . . . . . . . . . . .
SUPPLY FAN (BLOWER) SECTION 4 . . . . . . . . . . . . . .
COOLING 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PURON
R
(R--410A) REFRIGERANT 8 . . . . . . . . . . . . . .
THERMOSTATIC EXPANSION VALVE (TXV) 9 . . . . .
COOLING CHARGING CHARTS 10 . . . . . . . . . . . . . . . .
CONVENIENCE OUTLETS 14 . . . . . . . . . . . . . . . . . . . .
SMOKE DETECTORS 15 . . . . . . . . . . . . . . . . . . . . . . . . .
PROTECTIVE DEVICES 22 . . . . . . . . . . . . . . . . . . . . . . .
GAS HEATING SYSTEM 23 . . . . . . . . . . . . . . . . . . . . . .
ECONOMIZER SYSTEMS 34 . . . . . . . . . . . . . . . . . . . . .
COMFORTLINK (FACTORY OPTION) 34 . . . . . . . . . . .
RTU OPEN CONTROL SYSTEM 34 . . . . . . . . . . . . . . . .
VFD OPERATION WITH REMOTE KEYPAD 34 . . . . .
WIRING DIAGRAMS 35 . . . . . . . . . . . . . . . . . . . . . . . . .
PRE--START--UP 38 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
START--UP, GENERAL 38 . . . . . . . . . . . . . . . . . . . . . . . .
FASTENER TORQUE VALUES 40 . . . . . . . . . . . . . . . . .
APPENDIX I. MODEL NUMBER SIGNIFICANCE 41 .
APPENDIX II. PHYSICAL DATA 42 . . . . . . . . . . . . . . . .
APPENDIX III. FAN PERFORMANCE 44 . . . . . . . . . . .
UNIT START-UP CHECKLIST 49 . . . . . . . . . . . . . . . . . .
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment
can be hazardous due to system pressure and electrical
components. Only trained and qualified service personnel
should install, repair, or service air-conditioning
equipment. Untrained personnel can perform the basic
maintenance functions of replacing filters. Trained service
personnel should perform all other operations.
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.
Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloth for brazing operations. Have
fire extinguisher available. Read these instructions
thoroughly and follow all warnings or cautions attached to
the unit. Consult local building codes and National
Electrical Code (NEC) for special requirements.
Recognize safety information. This is the safety--alert
symbol
. When you see this symbol on the unit and in
instructions or manuals, be alert to the potential for
personal injury.
Understand the signal words DANGER, WARNING, and
CAUTION. These words are used with the safety--alert
symbol. DANGER identifies the most serious hazards
which
will
result in severe personal injury or death.
WARNING signifies a hazard which could result in
personal injury or death. CAUTION is used to identify
unsafe practices which
may
result in minor personal
injury or product and property damage. NOTE is used to
highlight suggestions which
will
result in enhanced
installation, reliability, or operation.