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54
Table 13 – Troubleshooting Chart
SYMPTOM
CAUSE
REMEDY
Compressor and condenser fan will not start.
Power failure
Call power company
Fuse blown or circuit breaker tripped
Replace fuse or reset circuit breaker
Defective contactor, transformer, or high--pressure,
loss--of--charge or low--pressure switch
Replace component
Insufficient line voltage
Determine cause and correct
Incorrect or faulty wiring
Check wiring diagram and rewire correctly
Thermostat setting too high
Lower thermostat temperature setting below
room temperature
Compressor will not start but condenser fan
runs
Faulty wiring or loose connections in compressor cir-
cuit
Check wiring and repair or replace
Compressor motor burned out, seized, or
Determine cause
internal overload open
Replace compressor
Defective run/start capacitor, overload, start relay
Determine cause and replace
One leg of 3--phase power dead
Replace fuse or reset circuit breaker
Determine cause
Low input voltage
Determine cause and correct
Three--phase scroll compressor
Scroll compressor is rotating in the wrong direction
Correct the direction of rotation by reversing the
makes excessive noise, and there may be a
low pressure differential.
3--phase power leads to the unit. Shut down unit
to allow pressures to equalize.
Compressor cycles (other than normally sat-
isfying thermostat)
Refrigerant overcharge or undercharge
Recover refrigerant, evacuate system, and re-
charge to capacities shown on rating plate
Defective compressor
Replace and determine cause
Insufficient line voltage
Determine cause and correct
Blocked outdoor coil
Determine cause and correct
Defective run/start capacitor
Determine cause and replace
Faulty outdoor fan motor or capacitor
Replace
Restriction in refrigerant system
Locate restriction and remove
Compressor operates continuously
Dirty air filter
Replace filter
Unit undersized for load
Decrease load or increase unit size
Thermostat temperature set too low
Reset thermostat
Low refrigerant charge
Locate leak, repair, and recharge
Air in system
Recover refrigerant, evacuate system, and re-
charge
Outdoor coil dirty or restricted
Clean coil or remove restriction
Excessive head pressure
Dirty air filter
Replace filter
Dirty condenser coil
Clean coil
Refrigerant overcharged
Recover excess refrigerant
Air in system
Recover refrigerant, evacuate system, and re-
charge
Condenser air restricted or air short--cycling
Determine cause and correct
Head pressure too low
Low refrigerant charge
Check for leaks, repair, and recharge.
Restriction in liquid tube
Remove restriction
Excessive suction pressure
Refrigerant overcharged
Recover excess refrigerant
Suction pressure too low
Dirty air filter
Replace filter
Low refrigerant charge
Check for leaks, repair and recharge
Metering device or low side restricted
Remove source of restriction
Insufficient evaporator airflow
Increase air quantity
Check filter–replace if necessary
Temperature too low in conditioned area
Reset thermostat
Outdoor ambient below 55
°
F (13
°
C)
Install low--ambient kit
Filter drier restricted
Replace filter
48V
L
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A
Summary of Contents for 48VL-A
Page 4: ...4 A09452 Fig 3 48VL A24 36 Unit Dimensions 48VL A ...
Page 5: ...5 A09453 Fig 4 48VL A42 60 Unit Dimensions 48VL A ...
Page 16: ...16 A09282 Fig 14 208 230 1 60 Connection Wiring Diagram 48VL A ...
Page 17: ...17 A09282 Fig 14 Cont 208 230 1 60 Ladder Wiring Diagram 48VL A ...
Page 18: ...18 A09264 Fig 15 208 230 3 60 Connection Wiring Diagram 48VL A ...
Page 19: ...19 A09264 Fig 15 Cont 208 230 3 60 Ladder Wiring Diagram 48VL A ...
Page 25: ...25 Table 7 Cooling Charging Chart A09083 48VL A ...