Carrier 68RF50 Neoplan-LA Operation manual

T-271
Bus Air
Conditioning
Unit
Model
68RF50
NEOPLAN-LA

OPERATION AND
SERVICE MANUAL
Carrier Transicold Division, Carrier Corporation, P.O. Box 4805, Syracuse, N.Y. 13221
Carrier Corporation 1996 DPrinted in U. S. A. 0496
BUS AIR CONDITIONING UNIT
MODEL
68RF50
NEOPLAN-LA

i
TABLE OF CONTENTS
Section Page
1 DESCRIPTION 1-1.........................................................
1.1 Introduction 1-1............................................................
1.2 Refrigeration System Component Specifications 1-5..............................
1.3 Electrical Specifications 1-6...................................................
1.4 Safety Devices 1-6...........................................................
1.5 System Operating Controls and Components 1-7.................................
1.6 Reheat Coolant Valve 1-9....................................................
1.7 Liquid Line Solenoid Valve 1-9................................................
1.8 Moisture/Liquid Indicator 1-9.................................................
1.9 Heater Coolant Flow Cycle 1-9................................................
1.10 Refrigeration Flow Cycle 1-10..................................................
2OPERATION 2-1...........................................................
2.1 Starting And Stopping Instructions 2-1.........................................
2.2 Pre-Trip Inspection 2-1.......................................................
2.3 Unit Operation 2-1..........................................................
2.3.1 Cooling (Air Conditioning) Cycle Operation - Cycling Clutch Control 2-1...
2.3.2 Cooling (Air Conditioning) Cycle Operation - Reheat Control 2-2..........
2.3.3 Heat Operation 2-3..................................................
3 TROUBLESHOOTING 3-1...................................................
3.1 Unit Will Not Cool 3-1.......................................................
3.2 Unit Runs But has Insufficient Cooling 3-1......................................
3.3 Abnormal Pressure 3-1.......................................................
3.4 Abnormal Noise and Vibrations 3-2............................................
3.4.1 Abnormal Noise 3-2..................................................
3.4.2 Abnormal Vibration 3-2...............................................
3.5 Temperature Controller Malfunction 3-2........................................
3.6 No Evaporator Air Flow or Restricted Air Flow 3-3..............................
3.7 Expansion Valve Malfunction 3-3..............................................
3.8 No Heating or Insufficient Heating 3-3.........................................
4SERVICE 4-1...............................................................
4.1 Maintenance Schedule 4-1....................................................
4.2 Suction and Discharge Service Valves 4-1.......................................
4.3 Manifold Gauge Set 4-1......................................................
4.4 System Pumpdown 4-2.......................................................
4.5 Removing Refrigerant Charge 4-2.............................................
4.6 Refrigerant Leak Check 4-3...................................................
4.7 Evacuation and Dehydration 4-3..............................................
4.8 Adding Refrigerant to System 4-5..............................................
4.9 Checking Refrigerant Charge 4-5..............................................
4.10 Filter-Drier Removal 4-6.....................................................
4.11 Checking Pressure Switches 4-6................................................
4.12 Thermostatic Expansion Valve 4-7.............................................
4.13 Removing the Heater Coil 4-8.................................................
4.14 Replacement of Evaporator Coil 4-8...........................................
4.15 Servicing the Reheat Coolant Valve 4-9.........................................
4.16 Servicing the Liquid Line Solenoid Valve 4-10....................................

ii
TABLE OF CONTENTS (CONT’D)
Section Page
4 SERVICE (CONT’D) 4-1.....................................................
4.17 Removing the Condenser Fan Motor 4-10........................................
4.18 Servicing the Evaporator Fan Blower Motor Assembly 4-11.........................
4.19 Replacing the Return Air Filters 4-11...........................................
4.20 Compressor 4-11.............................................................
4.20.1 Replacing the Compressor 4-11.........................................
4.20.2 Checking the Compressor Oil Level 4-12.................................
4.20.3 Adding Oil to the Installed Compressor 4-12..............................
4.20.4 Adding Oil to Service Replacement Compressor 4-13.......................
5ELECTRICAL
5.1 Introduction 5-1............................................................
LIST OF ILLUSTRATIONS
Figure Page
1-1 Evaporator Assembly - Top View 1-2..........................................
1-2 Condenser Assembly - Top View 1-3..........................................
1-3 Electrical Control Panel Components for Models with Rotron Brushless Motors 1-4..
1-4 Reheat Coolant Valve 1-9...................................................
1-5 Heater Coolant Flow Diagram 1-9............................................
1-6 Refrigeration Cycle Diagram 1-10.............................................
2-1 Temperature Controller Sequence During Cooling Mode 2-2.....................
2-2 Temperature Controller Sequence During Cooling with Reheat Mode 2-2..........
2-3 Temperature Controller Sequence During Heating Mode 2-3.....................
2-4 Cooling Cycle - High Speed Vent Mode Operation 2-4..........................
2-5 High Speed Unloaded (2-cylinder operation) Cool Mode Operation 2-5............
2-6 High Speed Semi-loaded (4-cylinder operation) Cool Mode Operation 2-6.........
2-7 High Speed Fully Loaded (6-cylinder operation) Cool Mode Operation 2-7.........
2-8 High Speed Unloaded (2-cylinder operation) Cool with Reheat Mode Operation 2-8.
2-9 Heating Cycle - Low Speed Heat Mode Operation 2-9...........................
4-1 Suction or Discharge Service Valve 4-1........................................
4-2 Gauge Manifold Set 4-2....................................................
4-3 Evacuation Manifold 4-4....................................................
4-4 Evacuation Set-Up 4-5......................................................
4-5 Filter Drier Removal 4-6....................................................
4-6 Checking High Pressure Switch 4-6...........................................
4-7 Thermostatic Expansion Valve 4-7............................................
4-8 Thermostatic Expansion Valve Bulb and Thermocouple 4-8......................
4-9 Reheat Coolant Valve Assembly 4-9..........................................
4-10 Liquid Line Solenoid Valve - Alco 4-10.........................................
4-11 Compressor Oil Charge Connections 4-13......................................
4-12 Compressor - Model O5G 4-13...............................................
5-1 Electrical Wiring Schematic Diagram (68RF50 with Rotron Brushless Motors),
Dwg. No. C-070-935, Rev C 5-2.............................................

iii/iv
LIST OF TABLES
Table Page
1-1 Model Chart 1-1...........................................................
1-2 Additional Support Manuals 1-1.............................................
1-3 Safety Devices 1-6.........................................................
4-1 Pressure Switch Continuity Check 4-7.........................................
4-2 R-134a Temperature - Pressure Chart 4-14......................................