Carrier BT30RF- EXPR Service & Installation Manual page 95

TROUBLE
COMPRESSOR STARTS
& RUNS BUT CYCLES
ON PROTECTOR.
STARTING CAPACITORS
BURNT OUT.
RUNNING CAPACITORS
BURNT OUT.
RELAYS BURNT OUT.
TROUBLESHOOTING
COMMON CAUSE
Low line voltage.
Additional current passing through
protector.
Suction pressure too high.
Discharge pressure too high.
Protector weak.
Running capacitor defective.
Stator partially shorted or grounded.
Inadequate motor cooling.
Compressor tight.
Unbalanced line (three-phase).
Discharge valve leaking or broken.
Short cycling.
Prolonged operation on starting
winding.
Relay contacts sticking.
Improper relay or incorrect relay setting.
Improper capacitor.
Capacitor terminals shorted by water.
Excessive line voltage.
High line voltage and light load.
Capacitor voltage rating too low.
Capacitor terminals shorted by water
Low line voltage.
Excessive line voltage.
Incorrect running capacitor.
Short cycling.
Relay vibrating.
Incorrect relay.
REMEDY
Bring up voltage.
Check for added fan motors and pumps
connected to wrong side of protector.
Check compressor for proper application.
Check ventilation, restrictions and overcharge.
Check current - replace protector if
defective.
Check capacitance. Replace if defective.
Check resistances; check for ground. Replace
if defective.
Correct cooling system.
Check oil level. Check for binding condition.
Check voltage of each phase. If not equal,
correct condition of unbalance.
Replace valve plate.
Reduce number of starts to 20 or less per
hour.
Reduce starting load (install crankcase
pressure limit valve), increase voltage if
low – replace relay if defective.
Clean contacts or replace relay.
Replace relay.
Check parts list for proper capacitor rating:
mfd. and voltage.
Install capacitors so terminals won't be wet.
Reduce line voltage to not over 10% above
rating of motor.
Reduce voltage if over 10% excessive.
Install capacitors with recommended voltage
rating
Install capacitors so terminals won't be wet.
Increase voltage to not less than 10% above
motor rating.
Reduce voltage to not more than 10% above
motor rating.
Replace with correct capacitor.
Reduce number of starts per hour.
Mount relay rigidly.
Use relay recommended for specific motor
compressor.
97