Carrier VECTOR 6500 - Abnormal Noise; Abnormal Pressure; No Evaporator Air Flow or Restricted Air Flow

9−6
62-11389
INDICATION/
TROUBLE
Possible Causes
Action/Refer-
ence Section
9.4.8 Abnormal Pressure
High discharge pressure
Condenser coil dirty 8.8.2
Condenser fans rotating backwards Check Wiring
Condenser fan inoperative Check
Refrigerant overcharge or noncondensibles 8.6.2
Discharge service valve partially closed Open
Low discharge pressure
Compressor valves(s) worn or broken 8.7.1
Low refrigerant charge 8.6.2
Suction modulation valve malfunction 8.8.5
Low suction pressure
Filter-drier partially plugged 8.8.3
Low refrigerant charge 8.6.2
Expansion valve malfunction 9.4.11
No evaporator air flow or restricted air flow 9.4.10
Excessive frost on evaporator coil 9.4.7
Evaporator fan rotating backwards Check Wiring
Suction modulation valve malfunction 8.8.5
Liquid or suction line service valve partially closed Open
High suction pressure
Compressor valves(s) worn or broken 8.7.1
Compressor gasket(s) defective 8.7.1
Heater contactor stuck closed Check
Suction and discharge
pressures tend to equalize
when unit is operating
Compressor valves defective 8.7.1
Compressor gasket(s) defective 8.7.1
9.4.9 Abnormal Noise
Compressor
Loose mounting bolts Tighten
Worn bearings 8.7.1
Worn or broken valves 8.7.1
Liquid slugging 9.4.11
Insufficient oil 8.7.5
Condenser or evaporator fan
Loose or striking shroud Check
Bearings defective 8.9.6/8.9.7
Bent shaft 8.9.6/8.9.7
Water pump belt Cracked or worn Replace
9.4.10 No Evaporator Air Flow Or Restricted Air Flow
Evaporator coil blocked
Frost on coil 8.8.9
Dirty coil 8.8.1
No or partial evaporator
air flow
Evaporator fan loose or defective 8.9.6
Evaporator fan rotating backwards 8.9.6
Evaporator air flow blocked Check