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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. 04-53480153-01
Printed in U.S.A.
Form 48LC-14-26-03SM
Pg 1
2-2020
Replaces: 48LC-14-26-02SM
Service and Maintenance Instructions
CONTENTS
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . 1
UNIT ARRANGEMENT AND ACCESS. . . . . . . . . . . . . 2
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Seasonal Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . 3
SUPPLY FAN (BLOWER) SECTION . . . . . . . . . . . . . . 3
Supply Fan (Belt-Drive) . . . . . . . . . . . . . . . . . . . . . . . . 3
COOLING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Evaporator Coil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Refrigerant System Pressure Access Ports . . . . . . . 6
Troubleshooting Cooling System. . . . . . . . . . . . . . . . 6
PURON® (R-410A) REFRIGERANT. . . . . . . . . . . . . . . 8
Refrigerant Charge. . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
COOLING CHARGING CHARTS . . . . . . . . . . . . . . . . . 9
Compressors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Filter Drier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Condenser-Fan Adjustment . . . . . . . . . . . . . . . . . . . 14
CONVENIENCE OUTLETS . . . . . . . . . . . . . . . . . . . . . 14
Wet in Use Convenience Outlet Cover. . . . . . . . . . . 15
Non-Powered Type. . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Unit-Powered Type. . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Fuse On Powered Type . . . . . . . . . . . . . . . . . . . . . . . 16
Using Unit-Mounted Convenience Outlets . . . . . . . 16
SMOKE DETECTORS. . . . . . . . . . . . . . . . . . . . . . . . . 16
System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Smoke Detector Locations . . . . . . . . . . . . . . . . . . . . 17
FIOP Smoke Detector Wiring and Response. . . . . . 17
Sensor and Controller Tests . . . . . . . . . . . . . . . . . . . 18
Detector Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
PROTECTIVE DEVICES . . . . . . . . . . . . . . . . . . . . . . . 21
Compressor Protection . . . . . . . . . . . . . . . . . . . . . . . 21
Control Circuit, 24-v. . . . . . . . . . . . . . . . . . . . . . . . . . 22
GAS HEATING SYSTEM . . . . . . . . . . . . . . . . . . . . . . 22
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Fuel Types and Pressures. . . . . . . . . . . . . . . . . . . . . 22
Flue Gas Passageways . . . . . . . . . . . . . . . . . . . . . . . 23
Combustion-Air Blower . . . . . . . . . . . . . . . . . . . . . . . 23
Burners and Ignitors . . . . . . . . . . . . . . . . . . . . . . . . . 23
Burner Ignition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Orifice Replacement . . . . . . . . . . . . . . . . . . . . . . . . . 26
Minimum Heating Entering Air Temperature . . . . . . 30
Troubleshooting Heating System. . . . . . . . . . . . . . . 30
PRE-START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
START-UP, GENERAL . . . . . . . . . . . . . . . . . . . . . . . .32
Unit Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Return-Air Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Outdoor-Air Inlet Screens . . . . . . . . . . . . . . . . . . . . .33
Compressor Mounting . . . . . . . . . . . . . . . . . . . . . . . .33
Internal Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Refrigerant Service Ports. . . . . . . . . . . . . . . . . . . . . .33
Compressor Rotation . . . . . . . . . . . . . . . . . . . . . . . . .33
Cooling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Main Burners. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Heating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Ventilation (Continuous Fan). . . . . . . . . . . . . . . . . . .33
RTU Open Control System. . . . . . . . . . . . . . . . . . . . .34
SystemVu™ (Factory Option) . . . . . . . . . . . . . . . . . .34
Integrated Staging Control (ISC) Board . . . . . . . . . .35
EconoMi$er® X (Factory Option) . . . . . . . . . . . . . . .37
Staged Air Volume (SAV™) with Variable Frequency
Drive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Multi-Speed VFD Display Kit (Field-Installed
Option). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
FASTENER TORQUE VALUES. . . . . . . . . . . . . . . . . .63
SEQUENCE OF OPERATION . . . . . . . . . . . . . . . . . . .63
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Cooling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Economizer (Optional) . . . . . . . . . . . . . . . . . . . . . . . .64
Low Ambient Cooling Operation down to 40°F
(4°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Heating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
APPENDIX A — MODEL NUMBER
NOMENCLATURE . . . . . . . . . . . . . . . . . . . . . . . . . .66
APPENDIX B — PHYSICAL DATA . . . . . . . . . . . . . . .67
APPENDIX C — FAN PERFORMANCE . . . . . . . . . . .70
APPENDIX D — WIRING DIAGRAMS . . . . . . . . . . . .81
START-UP CHECKLIST . . . . . . . . . . . . . . . . . . . . .CL-1
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 basic maintenance functions 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 precautions in the
literature, tags and labels attached to the unit, and other safety
precautions that may apply.
Follow all safety codes, including ANSI (American National
Standards Institute) Z223.1. Wear safety glasses and work gloves.
WeatherExpert
®
48LC**14-26
Single Package Rooftop Unit with Gas Heat/Electric Cooling
with Puron
®
(R-410A) Refrigerant
Содержание 48LC 14
Страница 27: ...27 Fig 38 Integrated Gas Control IGC Board RED LED STATUS...
Страница 81: ...81 Fig B Typical Electromechanical Control Wiring Diagram 48LC 14 26 APPENDIX D WIRING DIAGRAMS...
Страница 82: ...82 Fig C 48LC 14 26 Systemvu Control Schematic APPENDIX D WIRING DIAGRAMS...
Страница 83: ...83 Fig D 48LC 14 26 RTU Open Control Wiring Diagram APPENDIX D WIRING DIAGRAMS...
Страница 85: ......