GMC G Service Manual page 85

SUBJECT
Description.................................................................................................................................................................1B- 3
CCOT A/C System................................................................................................................................................. 1B- 3
Rear Interior Roof Mounted Systems (Suburban & G-Van).............................................................................. 1B- 3
System Components............................................................................................................................................. 1B- 3
Periodic Maintenance and Servicing...................................................................................................................1B- 4
System Operation - R/V & G-Van..................................................................................................................... 1B- 4
Functional Test - R/V & G-Van.......................................................................................................................... 1B- 4
Refrigerant-12 Operating Characteristics...............................................................................................................1B- 8
System Components, Temperature and Pressure Relationships.....................................................................1B- 8
Refrigerant and Oil Capacity................................................................................................................................ 1B- 8
Handling Refrlgerant-12........................................................................................................................................ 1B- 9
Handling Refrigerant Lines and Fittings.............................................................................................................1B- 9
Maintaining Chemical Stability............................................................................................................................ 1B-10
Refrigerant System Diagnosis................................................................................................................................. 1B-10
Insufficient Cooling "Quick-Check" Procedure..................................................................................................1B-10
System Performance Test.................................................................................................................................... 1B-10
Testing the Refrigerant System........................................................................................................................... 1B-11
Leak Testing the Refrigerant System..................................................................................................................1B-11
Pressure Sensing Switch..................................................................................................................................... 1B-11
Compressor Cut-Out Switches............................................................................................................................ 1 B-11
Electrical/Vacuum Trouble Diagnosis.....................................................................................................................1B-18
Operational Test.... ................................................................................................................................................1B-18
Vacuum System Diagnosis...................................................................................................................................... 1B-24
R/V and G-Van ......................................................................................................................................................1B-24
Evacuating and Charging Procedures....................................................................................................................1B-24
Discharging, Evacuating, Adding Oil and Charging Procedures......................................................................1B-24
Discharging the System....................................................................................................................................... 1B-26
Refrigerant Oil Distribution.................................................................................................................................. 1B-26
Evacuating and Charging..................................................................................................................................... 1B-27
Gage Calibration.................................................................................................................................................... 1B-27
Vacuum System Check......................................................................................................................................... 1B-27
Charging Station Method...................................................................................................................................... 1 B-27
Disposable Can or Multi-Can Method..................................................................................................................1B-27
Refrigerant Drum Method..................................................................................................................................... 1 B-27
Charging the System............................................................................................................................................ 1 B-27
Accumulator Assembly......................................................................................................................................... 1B-28
Specific Component Diagnosis............................................................................................................................... 1B-28
Compressor............................................................................................................................................................1B-28
Condenser..............................................................................................................................................................1 B-28
Expansion Valve....................................................................................................................................................1 B-28
Evaporator..............................................................................................................................................................1B-29
Refrigerant Line Restrictions............................................................................................................................... 1B-29
On-Vehicle Service.................................................................................................................................................... 1 B-29
Refrigerant-11 Flushing Procedure......................................................................................................................1B-29
Filter Installation.................................................................................................................................................... 1 B-29
Compressor Replacement (R/V)...........................................................................................................................1B-30
Compressor Replacement (G-Van).......................................................................................................................1B-30
A/C System - - R/V Series....................................................................................................................................... 1B-35
Condenser Replacement....................................................................................................................................... 1B-35
Accumulator Replacement................................................................................................................................... 1B-36
Blower Assembly Replacement........................................................................................................................... 1B-37
Evaporator Core Replacement............................................................................................................................. 1B-38
SECTION 1B
AIR CONDITIONING
CONTENTS
IB-1
PAGE