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INDICATION/
REFERENCE
TROUBLE
POSSIBLE CAUSES
SECTION
3-2
3.3 ABNORMAL PRESSURE CONT’D
Low suction pressure
Suction service valve partially closed
Open
Filter-drier inlet and outlet valves partially closed
Check/Open
Filter-drier partially plugged
4.10
Low refrigerant charge
4.9
Expansion valve malfunction
3.7
Restricted air flow
3.6
Liquid line solenoid malfunction
4.16
Low evaporator air flow
Blower running in reverse
Check/3-6 and/or
Reverse Motor
Electrical Leads
Dirty air filter
4.19
Icing of coil
Defrost and
Clean
Suction and discharge pressures
Compressor valves defective
See Note
tend to equalize when unit
is operating
3.4 ABNORMAL NOISE AND VIBRATIONS
3.4.1 ABNORMAL NOISE
Compressor
Loose mounting bolts
Check/Tighten
Worn bearings
See Note
Worn or broken valves
See Note
Liquid slugging
3.3
Insufficient oil
Check/4.20.2
Clutch loose or rubbing
Check/Tighten
Condenser or Evaporator fan
Loose or defective
4.17 & 4.18
Bearings
Replace
Blade Interference
4.17 & 4.18
Blade broken or missing
4.17 & 4.18
3.4.2 ABNORMAL VIBRATION
Compressor
Loose mounting bolts
Check/Tighten
Evaporator or Condenser fan
Bent shaft on motor
4.17 & 4.18
Blade broken or missing
4.17 & 4.18
3.5 TEMPERATURE CONTROLLER MALFUNCTION
Will not control
Controller defective
1.5.a/Replace
Sensor defective
Replace
Defective wiring
Check/Repair
NOTE: Refer to 05G Compressor manual, Form T-199.