Carrier 48HC Series - User Manual

48HC 3 to 12. 5 Nominal Tons
Single P ackage Ro oft op
Gas Heat/Electr ic Cooling Unit
with Puron ( R---410A) Refr ige rant
Sizes: 04–14
Service and Maintenance Instructions
TABLE OF CONTENTS
SAFETY CONSIDERATIONS 1....................
UNIT ARRANGEMENT AND ACCESS 3...........
RETURN AIR FILTERS 4.........................
SUPPLY FAN (BLOWER) SECTION 4..............
STAGED AIR VOLUME CONTROL --2 SPEED FAN
WITH VARIABLE FREQUENCY DRIVE (VFD) 8....
ADDITIONAL VARIABLE FREQUENCY DRIVE
(VFD) INSTALLATION AND TROUBLESHOOTING. 9
MOTOR 9......................................
COOLING 13...................................
THERMOSTATIC EXPANSION VALVE (TXV) 15....
PURONR (R--410A) REFRIGERANT 16.............
COOLING CHARGING CHARTS 18................
COMPRESSOR 22...............................
CONVENIENCE OUTLETS 25....................
SMOKE DETECTORS 26.........................
SENSOR AND CONTROLLER TESTS 30...........
PROTECTIVE DEVICES 33.......................
GAS HEATING SYSTEM 34......................
PREMIERLINK CONTROL 49...................
RTU--OPEN CONTROL SYSTEM 49................
SENSORY/ACCESSORY INSTALLATION 49........
ADDITIONAL RTU--OPEN INSTALLATION AND
TROUBLESHOOTING 50.........................
ECONOMIZER UNITS 52........................
PRE--START--UP/START--UP 60....................
START--UP, GENERAL 61........................
START--UP, PREMIERLINK CONTROLS 63.......
START--UP, RTU--OPEN CONTROLS 64............
FASTENER TORQUE VALUES 64.................
APPENDIX I. MODEL NUMBER SIGNIFICANCE 65.
APPENDIX II. PHYSICAL DAT A 66................
APPENDIX III. FAN PERFORMANCE 71...........
APPENDIX IV WIRING DIAGRAMS 90............
APPENDIX V. MOTORMASTER SENSOR
LOCATIONS 135................................
UNIT START-UP CHECKLIST 138.................
SAFETY CONSIDERAT I ONS
Installation and servicing of air-conditioning equipment
can be hazardous due to system pressure and electrical
compone nts. 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 ope rations.
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 informat ion. This is the safety ALERT
symbol
. When you see this symbol on the unit and in
instructions or manuals, be aware of the potential for
physical injury hazards.
Understand the signal words DANGER, WARNING,and
CAUTION. These words are used with the safety--ALERT
symbol. DANGER indicates a hazardous situation which,
if not avoided, will result in death or severe personal
injury. WARNING indicates a hazardous situation which,
if not avoided, could re sult in death or personal i njury.
CAUTION indicates a hazardous situation which, if not
avoide d, could result in minor to moderate injury or
product and property damage. NOTICE is used to address
practices not related to physical injury. NOTE is used to
highlight suggestions which will result in enhanced
installation, reliability, or operation.

Carrier 48HC Series Specifications