Troubleshooting - Carrier 38AKS028-044 Installation, Start-Up And Service Instructions Manual

SYMPTOM AND PROBABLE CAUSE
COMPRESSOR DOES NOT RUN
1. Control circuit breaker tripped
2. Power line open
3. Oil pressure switch tripped
4. Safety device tripped
5. Contactor stuck open
6. Loose terminal connection
7. Improperly wired controls
8. Seized compressor
9. Low line voltage
10. Compressor motor defective
COMPRESSOR STOPS ON LOW-PRESSURE
CONTROL
1. Compressor suction shutoff valve partially closed
2. Low refrigerant charge
3. Liquid line solenoid valve(s) fails to open
4. Liquid line shutoff valve closed
COMPRESSOR STOPS ON HIGH-PRESSURE
CONTROL
1. Compressor discharge valve partially closed
2. Air in system
3. Condenser fan(s) not operating
4. System is overcharged.
UNIT OPERATES TOO LONG OR
CONTINUOUSLY
1. Low refrigerant charge
2. Control contacts fused
3. Air in system
4. Partially plugged expansion valve or filter drier
SYSTEM IS NOISY
1. Piping vibration
2. Compressor noisy
COMPRESSOR LOSES OIL
1. Leak in system
2. Crankcase heaters not energized during
shutdown
3. Improper interconnecting piping design
FROSTED SUCTION LINE
1. Expansion valve admitting excess refrigerant
HOT LIQUID LINE
1. Shortage of refrigerant due to leak.
2. Expansion valve opens too wide
FROSTED LIQUID LINE
1. Restricted filter drier
COMPRESSOR WILL NOT UNLOAD
1. Defective unloader
2. Defective capacity control solenoid valve
3. Miswired liquid line solenoid
4. Weak, broken, or wrong valve body spring
COMPRESSOR WILL NOT LOAD
1. Miswired capacity control liquid solenoid
2. Defective capacity control solenoid valve
3. Plugged strainer (high side)
4. Stuck or damaged unloader piston or piston
ring(s)

TROUBLESHOOTING

PROBABLE REMEDY
1. Reset control circuit breaker
2. Reset circuit breaker
3. Reset oil pressure switch at unit
4. Reset control circuit with thermostat
5. Replace contactor
6. Check connections
7. Check and rewire
8. Check motor winding for open or short.
Replace compressor, if necessary
9. Check line voltage — determine location of
voltage drop and remedy deficiency
10. Check motor winding for open or short.
Replace compressor, if necessary
1. Open valve
2. Add refrigerant
3. Check liquid line solenoid valve for proper
operation. Replace if necessary
4. Open valve
1. Open valve or replace if defective
2. Purge and evacuate system
3. Check motor wiring and repair or replace if
defective
4. Reclaim charge as needed
1. Add refrigerant
2. Replace control
3. Purge and evacuate system
4. Clean or replace
1. Support piping as required
2. Check valve plates for valve noise. Replace
compressor if bearings are worn
1. Repair leak
2. Check wiring and relays. Check heater and
replace if defective
3. Check piping for oil return. Replace if
necessary
1. Adjust expansion valve
1. Repair leak and recharge
2. Adjust expansion valve
1. Remove restriction or replace
1. Replace
2. Replace valve
3. Rewire correctly
4. Replace spring
1. Rewire correctly
2. Replace valve
3. Clean or replace strainer
4. Clean or replace the necessary parts
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