Operating instructions

SYMPTOM
Compressor and condenser fan
will not start.
Compressor will not
start but condenser
fan runs,
Three-phase scroll compressor
(48GS048 and 48GX030-060 only)
makes excessive noise, and there may
be a low pressure dilferentiat.
Compressor cycles (other than
normally satisfying thermostat).
Compressor operates oonUnuously,
Excessive head pressure.
Head pressure too low.
Excessive suction pressure.
Suction pressure too low.
Table 16_Troubleshooting Guide_Cooling
CAUSE
Power Failure
Fuse blown or circuit breaker tdppad
Defective thermostat, contactor, transformer, or control relay
Insufficient line voltage
Incorrect or faulty widng
Thermostat setting too high
Faulty widng or loose connections in compressor circuit
Compressor motor burned out, seized, or internal
ovedoad open
Defective run/start capacitor, overload, start relay
One leg of 3-phase power dead
Scroll compressor is rotsting in the wrong direction
Refrigerant overcharge or undercharge
Defective compressor
insufficient line voltage
Blocked condenser
Defective _n/start capacitor, ovedoad or start relay
Defective thermostat
Faulty condenser-fan motor or capacitor
Restriction in refitgerant system
Dirty air filter
Unit undersized for load
Thermostat set too low
Low refrigerant charge
Leaking valves in compressor
Air in system
Condenser coil dirty or restricted
Dirty air filter
Dirty condenser COil
Refrigerant overcharged
Air in system
Condenser air restricted or air short_ysiing
Low refrigerant charge
Compressor valves leaking
Restriction in liquidtube
High heat load
Compressor valves leaking
Refrigerant overcharged
Dirty air filter
Low refitgerant charge
Mefedng device or low side restdcted
Insufficient evaporator airflow
Temperature too low in conditioned area
Outdoor ambient below 40°F
Fistd-instailed filter-alder restricted
REMEDY
Call power company.
Replace fuse or reset cimuit breaker.
Replace component.
Determine cause and correct.
Check widng diagram and rewire correctly.
Lower thermostat setting below room temperature.
Check wiring and repair or replace.
Determine cause
Replace compressor.
Determine cause and replace.
Replace fuse or reset circuitbreaker.
Determine cause.
Correct the direction of rotation by reversing the
3-phase power leads to the unit. Shut down unit
to allow pressures to equat_ze.
Recover refrigerant, evacuate system, and recharge to
capacities shown on nameplate.
Replace and determine cause.
Determine cause and correct.
Determine cause and correct.
Determine cause and replace.
Replace thermostat.
Replace.
Locate restriction and remove.
Replace filter.
Decrease load or increase unit size.
Reset thermostat.
Locate leak, repair, and recharge.
Replace compressor.
Recover refrigerant, evacuate system, and recharge.
Clean coil or remove restdction.
Replace filter.
Clean coil.
Recover excess refrigerant.
Recover refdgerant, evacuate system, and recharge.
Determine cause and correct.
Check for leaks, repair, and recharge.
Replace compressor.
Remove restriction.
Check for source and eliminate.
Replace compressor.
Recover excess refrigerant.
Replace Filter.
Check for leaks, repair, and recharge.
Remove source of restdction.
Increase air quantity. Check filter -- replace if necessary.
Reset thermostat.
install low-ambient kit.
Replace.
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