Carrier 48GS Installation, Start-Up, And Operating Instructions Manual

HEATING & COOLING
48GS, 48GX
3-Phase Single-Packaged Gas Heating/
Electric Cooling Units
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Installation, Start-Up, and Operating Instructions
48GS Sizes 030-060, 48GX Sizes 030-060
NOTE: Read the entire instruction manual before starting the
installation.
TABLE OF CONTENTS
SAFETY CONSIDERATIONS ..................................................... 1
INTRODUCTION .......................................................................... 2
RECEIVING AND INSTALLATION .......................................... 2
CHECK EQUIPMENT ............................................................. 2
IDENTIFY UNIT ................................................................ 2
INSPECT SHIPMENT ........................................................ 2
INSTALLATION ................................................................ 2
PROVIDE uNrr SUPPORT .................................................... 2
ROOF CURB ....................................................................... 2
SLAB MOUNT ................................................................... 2
GROUND MOUNT ............................................................ 6
FIELD FABRICATE DUCTWORK ........................................ 6
PROVIDE CLEARANCES ...................................................... 7
RIG AND PLACE UNIT ......................................................... 7
CONNECT CONDENSATE DRAIN ...................................... 7
INSTALL FLUE HOOD .......................................................... 8
INSTALL GAS PIPING ........................................................... 8
INSTALL DUCT CONNECTIONS ...................................... 10
CONFIGURING UNITS FOR DOWNFLOW (VERTI-
CAL) DISCHARGE .......................................................... 10
INSTALL ELECTRICAL CONNECTIONS ......................... 12
HIGH-VOLTAGE CONNECTIONS ................................ 12
SPECIAL PROCEDURES FOR 208-V OPERATION ...12
CONTROL VOLTAGE CONNECTIONS ....................... 12
HEAT ANTICIPATOR SETTING ................................... 12
TRANSFORMER PROTECTION .................................... 15
PRE-START-UP .......................................................................... 15
START-HE ................................................................................... 15
CHECK FOR REFRIGERANT LEAKS ............................... 15
START-UP HEATING AND MAKE ADJUSTMENTS......16
CHECK HEATING CONTROL ....................................... 16
CHECK GAS INPUT ........................................................ 16
ADJUST GAS INPUT ...................................................... 16
CHECK BURNER FLAME .............................................. 19
AIRFLOW AND TEMPERATURE RISE ....................... 19
HEATING SEQUENCE OF OPERATION ..................... 19
LIMIT SWITCHES ........................................................... 19
AUXILIARY LIMIT SWITCH (ROLLOUT) .................. 19
START-UP COOLING AND MAKE ADJUSTMENTS......20
CHECKING COOLING CONTROL OPERATION .......20
CHECKING AND ADJUSTING REFRIGERANT
CHARGE ........................................................................... 20
INDOOR AIRFLOW AND AIRFLOW ADJUST-
MENTS .............................................................................. 21
COOLING SEQUENCE OF OPERATION ..................... 21
MAINTENANCE ......................................................................... 21
AIR FILTER ...................................................................... 24
EVAPORATOR BLOWER AND MOTOR ..................... 24
FLUE GAS PASSAGEWAYS ......................................... 26
A99338
Fig. 1--Unit 48GS and 48GX
COMBUSTION-AIR BLOWER ....................................... 27
LIMIT SWITCH ................................................................ 27
BURNER IGNITION ........................................................ 27
MAIN BURNERS ............................................................. 27
CONDENSER COIL, EVAPORATOR COIL, AND
CONDENSATE DRAIN PAN .......................................... 27
CONDENSER FAN .......................................................... 28
ELECTRICAL CONTROLS AND WIRING .................. 28
REFRIGERANT CIRCUIT ............................................... 28
GAS INPUT ...................................................................... 28
EVAPORATOR AIRFLOW ............................................. 28
METERING DEVICE -- ACUTROL DEVICE ............. 28
LIQUID LINE STRAINER .............................................. 28
TROUBLESHOOTING ............................................................... 28
START-UP CHECKLIST ............................................................ 28
NOTE TO INSTALLER-- Before the installation, READ THESE
INSTRUCTIONS CAREFULLY AND COMPLETELY. Also,
make sure the User's Manual and Replacement Guide are left with
the unit after installation. The furnace is NOT to be used for
temporary beating of buildings or structures under construction.
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment can be
hazardous due to system pressure and electrical components. Only
trained and qualified personnel should install repair, or service
air-conditioning equipment.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring otiligations.
PC 101 Printed ir_ U.S.A. Catalog NO. 48GS,GX-TSI Pg 1 2-06 Replaces: New