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Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 04-53480156-01
Printed in U.S.A.
Form 48HC-4-14-03SM Rev. C
Pg 1
10-19
Replaces: 48HC-4-14-02SM
Service and Maintenance Instructions
CONTENTS
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . 2
UNIT ARRANGEMENT AND ACCESS. . . . . . . . . . . . . 3
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Seasonal Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . 3
RETURN AIR FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . 3
Outside Air Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Economizer Inlet Air Screen . . . . . . . . . . . . . . . . . . . . 4
Manual Outside Air Hood Screen . . . . . . . . . . . . . . . . 4
SUPPLY FAN (BLOWER) SECTION . . . . . . . . . . . . . . 4
Supply Fan (Direct-Drive) . . . . . . . . . . . . . . . . . . . . . . 4
Supply Fan (Belt-Drive) . . . . . . . . . . . . . . . . . . . . . . . . 6
Belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
STAGED AIR VOLUME CONTROL — 2 SPEED FAN
WITH VARIABLE FREQUENCY DRIVE (VFD) . . . . 7
Staged Air Volume (SAV) Indoor Fan Speed
System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Identifying Factory Option . . . . . . . . . . . . . . . . . . . . . 7
Unit Installation with SAV Option . . . . . . . . . . . . . . . . 8
ADDITIONAL VARIABLE FREQUENCY DRIVE (VFD)
INSTALLATION AND TROUBLESHOOTING . . . . . 8
MOTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Replacing the Motor. . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Changing Fan Wheel Speed . . . . . . . . . . . . . . . . . . . . 9
REMOTE VFD KEYPAD REFERENCE . . . . . . . . . . . . 9
COOLING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Condenser Coil. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Condenser Coil Maintenance and Cleaning
Recommendation. . . . . . . . . . . . . . . . . . . . . . . . . . 12
Evaporator Coil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
THERMOSTATIC EXPANSION VALVE (TXV) . . . . . . 13
TXV Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Replacing TXV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Refrigerant System Pressure Access Ports . . . . . . 14
PURON® (R-410A) REFRIGERANT. . . . . . . . . . . . . . 15
Refrigerant Charge. . . . . . . . . . . . . . . . . . . . . . . . . . . 15
COOLING CHARGING CHARTS . . . . . . . . . . . . . . . . 15
COMPRESSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Replacing Compressor . . . . . . . . . . . . . . . . . . . . . . . 18
Compressor Rotation . . . . . . . . . . . . . . . . . . . . . . . . 18
Filter Drier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Condenser-Fan Adjustment . . . . . . . . . . . . . . . . . . . 18
CONVENIENCE OUTLETS . . . . . . . . . . . . . . . . . . . . . 20
SMOKE DETECTORS . . . . . . . . . . . . . . . . . . . . . . . . . 21
System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Smoke Detector Sensor . . . . . . . . . . . . . . . . . . . . . . .21
Smoke Detector Locations. . . . . . . . . . . . . . . . . . . . .22
Completing Installation of Return Air Smoke
Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
FIOP Smoke Detector Wiring and Response . . . . . .23
SENSOR AND CONTROLLER TESTS . . . . . . . . . . . .24
Sensor Alarm Test . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Controller Alarm Test . . . . . . . . . . . . . . . . . . . . . . . . .24
Dirty Controller Test . . . . . . . . . . . . . . . . . . . . . . . . . .24
Dirty Sensor Test . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Dirty Sensor Test Procedure . . . . . . . . . . . . . . . . . . .25
Changing the Dirt Sensor Test . . . . . . . . . . . . . . . . .25
Remote Station Test . . . . . . . . . . . . . . . . . . . . . . . . . .25
SD-TRK4 Remote Alarm Test Procedure . . . . . . . . .25
Remote Test/Reset Station Dirty Sensor Test . . . . .25
Dirty Sensor Test Using an SD-TRK4 . . . . . . . . . . . .26
Detector Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Indicators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
PROTECTIVE DEVICES . . . . . . . . . . . . . . . . . . . . . . .27
Compressor Protection . . . . . . . . . . . . . . . . . . . . . . .27
Relief Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Control Circuit, 24-V . . . . . . . . . . . . . . . . . . . . . . . . . .27
GAS HEATING SYSTEM . . . . . . . . . . . . . . . . . . . . . . .28
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Fuel Types and Pressures . . . . . . . . . . . . . . . . . . . . .28
Flue Gas Passageways . . . . . . . . . . . . . . . . . . . . . . .29
Combustion-Air Blower . . . . . . . . . . . . . . . . . . . . . . .29
Burners and Igniters. . . . . . . . . . . . . . . . . . . . . . . . . .31
Removing the Heat Exchanger . . . . . . . . . . . . . . . . .32
Burner Ignition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Orifice Replacement . . . . . . . . . . . . . . . . . . . . . . . . . .33
Troubleshooting Heating System . . . . . . . . . . . . . . .42
PremierLink™ Control . . . . . . . . . . . . . . . . . . . . . . . .43
RTU Open Control System. . . . . . . . . . . . . . . . . . . . .43
ECONOMIZER SYSTEMS . . . . . . . . . . . . . . . . . . . . . .43
EconoMi$er IV Standard Sensors . . . . . . . . . . . . . . .49
EconoMi$er IV Control Modes . . . . . . . . . . . . . . . . . .49
EconoMi$er IV Preparation . . . . . . . . . . . . . . . . . . . .53
Differential Enthalpy . . . . . . . . . . . . . . . . . . . . . . . . . .53
Single Enthalpy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
DCV (Demand Controlled Ventilation) and Power
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
DCV Minimum and Maximum Position . . . . . . . . . . .53
Supply-Air Sensor Input. . . . . . . . . . . . . . . . . . . . . . .53
EconoMi$er IV Troubleshooting Completion . . . . . .54
EconoMi$er® X (Factory Option) . . . . . . . . . . . . . . .54
PRE-START-UP/START-UP . . . . . . . . . . . . . . . . . . . .68
WeatherMaster
®
48HC04-14
Single Package Rooftop Gas Heat/Electric Cooling Unit
with Puron
®
(R-410A) Refrigerant
Summary of Contents for WeatherMaster 48HC04 Series
Page 37: ...37 Fig 60 Integrated Gas Control IGC Board RED LED STATUS ...
Page 45: ...45 Fig 65 RTU Open Overlay for Economizer Wiring ...
Page 46: ...46 Fig 66 VFD Overlay for W2770 Controller Wiring ...
Page 98: ...98 Fig E 48HC A07 YAC Control Diagram 208 230 3 60 460 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 100: ...100 Fig G 48HC D11YAC Control Diagram 208 230 3 60 460 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 101: ...101 Fig H 48HC D12 YAC Control Diagram 208 230 3 60 460 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 102: ...102 Fig I 48HC A04 A06 YAC Power Diagram 208 230 1 60 APPENDIX D WIRING DIAGRAMS ...
Page 103: ...103 Fig J 48HC A04 A06 YAC Power Diagram 208 230 3 60 460 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 104: ...104 Fig K 48HC A04 A06 YAC Power Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 107: ...107 Fig N 48HC A07 A12 YAC Power Diagram 208 230 3 60 460 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 108: ...108 Fig O 48HC A07 A12 YAC Power Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 109: ...109 Fig P 48HC D08 D09 YAC Power Diagram 230 460 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 110: ...110 Fig Q 48HC D08 D09 YAC Power Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 111: ...111 Fig R 48HC D11 YAC Power Diagram 208 230 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 112: ...112 Fig S 48HC D11 YAC Power Diagram 460 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 113: ...113 Fig T 48HC D11 YAC Power Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 114: ...114 Fig U 48HC D12 YAC Power Diagram 230 460 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 115: ...115 Fig V 48HC D12 YAC Power Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 116: ...116 Fig W 48HC D14 YAC Control Diagram 208 230 3 60 460 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 117: ...117 Fig X 48HC D14 YAC Power Diagram 208 230 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 118: ...118 Fig Y 48HC D14 YAC Power Diagram 460 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 119: ...119 Fig Z 48HC D14 YAC Power Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 142: ...142 Fig AW PremierLink System Control Wiring Diagram System APPENDIX D WIRING DIAGRAMS ...
Page 144: ...144 Fig AY RTU Open Wiring Diagram APPENDIX D WIRING DIAGRAMS ...