Carrier /50HC 04-28 User Manual

Cont ro ls , St art---Up, Operat io n
and Troubleshooting
48/50HC 04---28
Single Package Rooftop Units
with ComfortLink Controls Version 1.X
and PURONr (R---410A) Refrigerant
IMPORTANT: This literature covers 48/50HC 04--28 models with
ComfortLink Software version 1.X.
TABLE OF CONTENTS
Page
SAFETY CONSIDERATIONS 2.........................
GENERAL 3.........................................
BASIC CONTROL USAGE 3...........................
ComfortLink Control 3................................
Scrolling Marquee 3..................................
Accessory Navigator Display 4..........................
Operation 4.........................................
System Pilott and Touch Pilot Devices 4.................
CCN Tables and Display 4.............................
Conventions Used in This Manual 6......................
START--UP 6.........................................
Unit Preparation 6....................................
Compressor Mounting 6...............................
Refrigerant Service Ports 6.............................
Crankcase Heater(s) 6.................................
Compressor Rotation 6................................
Power Supply 6.....................................
Internal Wiring 6.....................................
Evaporator Fan 6....................................
Condenser Fans and Motors 7...........................
Return--Air Filters 7..................................
Outdoor--Air Inlet Screens 7............................
Accessory Installation 7...............................
Orifice Change (48HC) 7..............................
Gas Heat (48HC) 8...................................
EnergyX 8.........................................
CONTROLS QUICK SET--UP 9.........................
Control Set Point and Confirmation Log 9.................
Thermostat Control 9.................................
Space Temperature Sensor Control -- Direct Wired
(T--55 or T--56 or T--59) 9.............................
T--58 Communicating Room Sensor 9....................
CCN Linkage Control 9...............................
System Pilot -- Communication Space Sensor 9.............
Thermidistat Control 9................................
Space Humidistat Control 9............................
Relative Humidity Sensor Control 9......................
CCN Communication 9...............................
Accessories 9.......................................
Programming Operating Schedules 10....................
SERVICE TEST 12....................................
Independent Outputs 12...............................
Fan Test 12.........................................
Cooling Test 12.....................................
Humidi--MiZert Test 12..............................
Heating Test 13......................................
THIRD PARTY CONTROL 13..........................
Cooling/Heating Control 13............................
Dehumidification Control 13...........................
Remote Occupancy 13................................
Fire Shutdown 13....................................
Alarm Output 13.....................................
Economizer Damper Control 13.........................
CONTROLS OPERATION 14...........................
Display Configuration 14..............................
Unit Configuration 14.................................
Modes 14..........................................
General Operation 15.................................
Temperature Setpoint Determination 15...................
Occupancy Determination 16...........................
Cooling Operation 18.................................
Heating Operation 19.................................
Economizer 21......................................
Indoor Air Quality (IAQ) 23............................
Optional Humidi--MiZert Dehumidification System 24......
EnergyX 29........................................
Temperature Compensated Start 29.......................
Carrier Comfort Network (CCN)R Configuration 30.........
Demand Limit 30....................................
Linkage 31.........................................
Alarm Handling 31...................................
TROUBLESHOOTING 31..............................
Complete Unit Stoppage 32............................
Restart Procedure 32..................................

Carrier /50HC 04-28 Specifications

General

Brand	Carrier
Model	/50HC 04-28
Category	Air Conditioner
Language	English

Summary

Safety Considerations

Electrical Shock Hazard

Warning about potential personal injury or death from electrical shock.

Unit Damage Hazard

Caution regarding potential equipment damage from improper procedures.

Start-Up Procedures

Unit Preparation

Steps to ensure the unit is installed correctly before start-up.

Compressor Rotation

Power Supply

Controls Quick Set-Up

Thermostat Control

Space Temperature Sensor Control -- Direct Wired

Service Test Modes

Independent Outputs

Testing economizer, exhaust fans, and alarm relay outputs.

Cooling Test

Testing individual compressors and related fan operations.

Humidi--MiZert Test

Controls Operation

Unit Configuration

Configuring factory options and field accessories.

Cooling Operation

Cooling Mode Control

Compressor Control

Heating Operation

Heating Mode Control

Staging Control

Methods for staging heating based on thermostat or sensor inputs.

Economizer

Reheat Control

Troubleshooting

Alarm Handling

Understanding and responding to system alerts and alarms.

Complete Unit Stoppage

Diagnosing and resolving conditions causing unit shutdown.

Diagnostic Alarm Codes and Possible Causes

Detailed list of alarm codes and their potential causes.

Cooling Troubleshooting

Compressor and Fan Will Not Start

Troubleshooting steps when the compressor or fan fails to start.

Compressor not running but ComfortLink Status show it is on

Humidi--MiZert Troubleshooting

Economizer Troubleshooting

Damper Does Not Move

Heating Troubleshooting

Heat Will Not Turn On

Steps to resolve issues when the unit does not initiate heating.

Burners Will Not Ignite

Troubleshooting steps for gas burners failing to ignite.

Phase Loss Protection

Phase Reversal Protection

Protection against incorrect three-phase power relationships.

Phase Loss Protection

Protection against loss of one or more phase inputs.

Thermistor Troubleshooting

Thermistor/Temperature Sensor Check

Major System Components

Main Base Board (MBB)

Overview of the MBB as the central control system component.

Economizer Control Board (ECB)

Appendix A — Local Display and CCN Tables

Mode — Service Test

Mode — Configuration

Table of configuration parameters, ranges, defaults, and CCN points.

Appendix C — Variable Frequency Drive (VFD)

VFD Diagnostics

Understanding VFD error reporting through LEDs and control panel.

Faults (Red LED Lit)

Interpreting VFD faults indicated by red LED and fault codes.

Alarms (Green LED Flashing)

Interpreting VFD alarms indicated by green LED and alarm codes.

Unit Start-Up Checklist

I. Pre-Start-Up

Pre-start-up verification steps for installation and packaging removal.

II. Start-Up Electrical

II. Start-Up Temperatures

II. Start-Up Pressures