Table Of Contents - Carrier SINGLE PACKAGE ROOFTOP UNITS ELECTRIC COOLING/GAS HEATING 48EJ Installation And Service Instructions Manual

Table of Contents

Safety Considerations1
Installation1
Provide Unit Support1
Table Of Contents1
Alternate Unit Support2
Roof Mount2
Step 2 - Rig And Place Unit2
Step 3 - Field Fabricate Ductwork2
Roof Curb3
Unit Leveling Tolerances Dimensions4
Vfd — Variable Frequency Drive5
Base Unit Dimensions, 48Ej,Ek024-0345
Base Unit Dimensions, 48Ew,Ey024-0347
Base Unit Dimensions, 48Ew,Ey038-0488
Rigging Label9
Physical Data10
Evaporator Fan Motor Data12
Air Distribution — Thru-The-Bottom12
Air Distribution — Thru-The-Side12
Step 4 - Install Flue Hood12
Field Gas Piping13
Step 5 — Trap Condensate Drain13
Step 6 — Install Gas Piping13
Step 7 — Controls Options13
Controls Options And Configurations14
Variable Air Volume (Vav) Applications15
Indoor Air Quality Sensor Configuration15
Field Control Remote Start/Stop15
Power Wiring16
Field Power Supply16
Routing Through Bottom Of Unit16
Step 8 - Make Electrical Connections16
Control Board Diagram17
Electrical Data18
Field Control Wiring21
Sensor Wiring (Cv Or Vav)21
Heat Interlock Relay21
Field Power Wiring Connections21
Control Box Diagram (Sizes 038-048)22
Field Control Thermostat Wiring22
Field Control Temperature Sensor Wiring22
Remote Field Control23
Carrier Comfort Network Interface23
Ccn Connection Approved Shielded Cables23
Space Temperature Averaging Wiring23
Color Code Recommendations24
Make Outdoor-Air Inlet Adjustments24
Economizer24
Economizer Hood Assembly24
Step 9 - Make Outdoor-Air Inlet24
Adding Seal Strip To Top Of Hood Sides25
Economizer Settings26
Adding Foam Strip To Hood Side26
Adding Foam Strip To Blockoff Baffle26
Accessory Differential Enthalpy Control26
Differential Enthalpy Sensor Installation27
Disable Economizer27
Attaching Seal Strip To Filter Cover27
Differential Enthalpy Control And Sensor27
Wiring Connections For Solid-State Enthalpy Control (Hh57Ac077)28
Psychrometric Chart For Enthalpy Control28
Economizer Details28
Position Power Exhaust/Barometric Relief Damper Hood29
Vav Duct Pressure Transducer29
Vav Building Pressure Transducer29
Install Field-Fabricated Wind Baffles30
Electrical Connections30
Pressure Transducer Locations30
Step 11 — Install All Accessories30
Start-Up31
Refrigerant Service Ports31
Crankcase Heaters31
Variable Frequency Drive (Vfd)31
Adjustments31
Power Exhaust32
Vfd Factory-Installed Jumpers32
Vfd Supply Air Pressure Set Point32
Potentiometer Signal Levels33
Crankcase Heater33
Evaporator Fan33
Condenser Fans And Motors33
Power Exhaust Default Set Points34
Dip Switch Configuration34
Dip Switch Factory Settings34
Fan Performance, 48Ej/Ek024-034 — Vertical Discharge Units35
Available External Static Pressure35
Fan Performance, 48Ej,Ek038,044 — Vertical Discharge Units36
Fan Performance — Power Exhaust38
Motor Limitations38
High Efficiency Motors38
Standard Efficiency Motors38
Air Quantity Limits39
Return-Air Filters39
Filter Replacement39
Outdoor-Air Inlet Screens39
User Defined Set Points40
Cooling, Variable Volume Units40
Gas Heating, Constant Volume (Cv) Units41
Gas Heating, Variable Air Volume (Vav) Units41
Morning Warm-Up (Vav Only)41
Morning Warm-Up42
Space Temperature Reset Sensor42
Heat Interlock Relay Wiring42
Smoke Control Modes43
Field-Supplied Smoke Detector Wiring43
Supply Air Temperature Reset43
Power Exhaust Operation43
Service44
Time Guard Circuit44
Head Pressure Control44
Capacity Control, Cooling44
Lubrication45
Main Burners45
Flue Gas Passageways45
Combustion-Air Blower45
Evaporator Fan Service And Replacement46
Belt Tension Adjustment46
Typical Gas Heating Section46
Gas Heat Section Details46
Evaporator-Fan Motor Replacement47
Condenser-Fan Adjustment47
Power Failure47
Gas Valve Adjustment47
Main Burner Removal48
Compressor Protection48
Overcurrent48
Overtemperature48
Evaporator Fan Motor Protection49
Condenser-Fan Motor Protection49
High- And Low-Pressure Switches49
Compressor Lockout Logic49
Typical Wiring Schematics50
Typical Vav 115-V Control Circuit52
Typical Cv 115-V Control Circuit53
Typical Vav 24-V Control Circuit54
Typical Cv 24-V Control Circuit55
Troubleshooting56
Typical Refrigerant Circuiting56
Typical Refrigerant Circuiting (48Ej,Ek,Ew,Ey038,044)57
Igc Control Scheme (Heating And Cooling)59
Alarm Codes For The Igc Control Board60
Igc Control Board Led Alarms60
Control Board Led Alarms60
Diagnostic Leds60
I/O Channel Designations Base Module — Cv61
I/O Channel Designations Base Module — Vav61
I/O Channel Designations Expansion Module (Field-Installed)61
Packaged Service Training62
Start-Up Checklist63
Pre-Start-Up63