CHUNLAN FRD50-B - Page 106

Troubleshooting
- 104 -
Failure Phenomena Failure analysis
Phase sequence
(absence) protection
Wire controller displays E6, only
put it to operation after re
-powerup
Check for correct compressor power phase
sequence;
Check for protection action in compressor;
Check for phase absence in compressor power
line;
Check for damaged compressor;
Check for damaged triode on main control board;
Check for damaged LM339N on outdoor board;
Check for bad connection of ID/OD connecting
cable;
Check for damaged OD board current transformer
Overcurrent
protection
Wire controller displays E7, only
put it to operation after re
-powerup
Check if 8HP compressor current exceeds 18A;
Check if 10HP compressor current exceeds 28A;
Check for damaged OD board LM339N;
Check for damaged triode on main control board;
Check for bad contact at ID/OD connecting cable;
Check for damaged OD board current transformer
Load relief
protection
Wire controller displays E8, only
put it to operation after re
-powerup
Check for normal cooling system;
During cooling, check if OD pipe temperature
sensor exceeds 70℃
During heating, check if ID pipe temperature
sensor exceeds 68℃
LV switch protection
Wire controller displays E9, only
put it to operation after re
-powerup
LV switch shall be ON; check for bad contact at
card connection;
Check for bad contact at ID?OD connecting cable
card connection
Schedule of other common failures of FR180/S and FR260/S air conditioner PCB board:
Phenomena Method of correction
Remote
control failure
Check for normal remote control receiver;
Check for normal remote control transmitter;
Check for normal remote controller
Remote
controller
failure
Check for normal 3V batteries;
Check crystal oscillator circuit;
Check for normal transmitter;
Check for displaced or bad contact in conducting rubber