*And Associated Modular Units - Carrier FLOTRONIC II 30GN040-420 Operating And Troubleshooting Manual

SYMPTOMS
COMPRESSOR DOES
NOT RUN
COMPRESSOR CYCLES OFF
ON LOW PRESSURE
COMPRESSOR SHUTS DOWN
ON HIGH PRESSURE
CONTROL
UNIT OPERATES LONG OR
CONTINUOUSLY
SYSTEM NOISES
COMPRESSOR LOSES OIL
FROSTED SUCTION LINE
HOT LIQUID LINE
FROSTED LIQUID LINE
COMPRESSOR DOES NOT
UNLOAD
COMPRESSOR DOES NOT
LOAD
EXV — Electronic Expansion Valve
Table 19 — Troubleshooting
CAUSE
Power line open
Control fuse open
High-Pressure Switch (HPS)
tripped
Tripped power breaker
Loose terminal connection
Improperly wired controls
Low line voltage
Compressor motor defective
Seized compressor
Loss of charge
Bad transducer
Low refrigerant charge
High-pressure control erratic in action
Compressor discharge valve partially closed
Condenser fan(s) not operating
Condenser coil plugged or dirty
Low refrigerant charge
Control contacts fused
Partially plugged or plugged expansion
valve or filter driver
Defective insulation
Service load
Inefficient compressor
Piping vibration
Expansion valve hissing
Compressor noisy
Leak in system
Mechanical damage (blown piston or
broken discharge valve)
Crankcase heaters not energized
during shutdown
Expansion valve admitting either too
much or too little refrigerant
Shortage of refrigerant due to leak
Shutoff valve partially closed or restricted
Burned out coil
Defective capacity control valve
Miswired solenoid
Weak, broken, or wrong valve body spring
Miswired solenoid
Defective capacity control valve
Plugged strainer (high side)
Stuck or damaged unloader piston or
piston ring(s)
Table 20 — Standard and Accessory Unloaders
NO. OF STANDARD
UNIT
UNLOADER(s)
30GN040-070 1
30GN080-170* 2
30GN190-210* 0

*And associated modular units.

REMEDY
Reset circuit breaker.
Check control circuit for ground or short.
Replace fuse.
Move LOCAL/ENABLE-STOP-CCN switch to STOP
position then back to RUN or CCN position.
Check the controls. Find cause of trip
and reset breaker.
Check connections.
Check wiring and rewire.
Check line voltage. Determine location
of voltage drop and remedy deficiency.
Check motor winding for open or short.
Replace compressor if necessary.
Replace compressor.
Repair leak and recharge.
Replace transducer.
Add refrigerant.
Replace control.
Open valve or replace if defective.
Check wiring. Repair or replace motor(s)
if defective.
Clean coil.
Add refrigerant.
Replace control.
Clean or replace.
Replace or repair.
Keep doors and windows closed.
Check valves. Replace if necessary.
Support piping as required.
Add refrigerant.
Check for plugged liquid line filter drier.
Check valve plates for valve noise.
Replace compressor (worn bearings).
Check for loose compressor holddown bolts.
Repair leak.
Repair damage or replace compressor.
Replace heaters, check wiring and
crankcase heater relay contacts.
Check cooler and compressor thermistors.
Test EXV.
Repair leak and recharge.
Open valve or remove restriction.
Replace coil.
Replace valve.
Rewire correctly.
Replace spring
Rewire correctly.
Replace valve.
Clean or replace strainer.
Clean or replace the necessary parts.
NO. OF ACCESSORY
UNLOADERS
PERMITTED
Circuit A Circuit B
1 1 or 2
1 1
1 1
66