33
No.
Symptom
LED indication
Abnormal point/
Condition
Condition Remedy
21
Outdoor unit
operates.
7-time fl ash
2.5 seconds OFF
Low discharge tem-
perature protection
Temperature of discharge temperature thermistor has been
50°C or less for 20 minutes.
• Refer to 11-5. "Check of LEV".
• Check the refrigerant circuit and
the refrigerant amount.
22
8-time fl ash
2.5 seconds OFF
MUFZ-KJ25/35
PAM protection
PAM: Pulse Ampli-
tude Modulation
The overcurrent fl ows into PFC (Power factor correction
:IC820) or the bus-bar voltage reaches 394 V or more, PAM
stops and restarts.
This is not malfunction. PAM pro-
tection will be activated in the fol-
lowing cases:
1 Instantaneous power voltage
drop. (Short time power failure)
2 When the power supply voltage
is high.
MUFZ-KJ50
Zero cross detecting
circuit
Zero cross signal cannot be detected.
• It occurs with following cases.
1 Instantaneous power voltage
drop. (Short time power failure)
2 Distortion of primary voltage
• Refer to 11-5. "Check of power
supply".
23
9-time fl ash
2.5 seconds OFF
Inverter check mode The connector of compressor is disconnected, inverter check
mode starts.
• Check if the connector of the com-
pressor is correctly connected.
Refer to 11-5. "How to check
inverter/compressor".
NOTE:
1. The location of LED is illustrated at the right fi gure. Refer to 11-6.1.
2. LED is lighted during normal operation.
The fl ashing frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the fl ashing frequency is “2”.
ON
OFF
2.5-second OFF
2.5-second OFF
0.5-second ON
0.5-second ON
LED
Flashing
→
Inverter P.C. board
MUFZ-KJ25/35VEHZ
MUFZ-KJ50VEHZ
LED
→
Flashing
OBH668E
