Mitsubishi Electric MUZ-A09YV-E1 Service Manual page 24

Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy
1. Troubleshooting check table
NOTE 1. The location of LED is illustrated at the right figure. Refer to page 32.
2. LED lights up during normal operation.
Symptom
No. LED indication
1-time flash every
Outdoor unit
2.5 seconds
1 does not
operate
NOTE:
For abnormality
2
location, refer to
'Indoor
troubleshooting
check table'.
3 Refer to service
manual OB327.
4
2-time flash
'Outdoor unit
2.5 seconds OFF
5
stops and
restarts 3
minutes later'
3-time flash
is repeated
2.5 seconds OFF
6
4-time flash
2.5 seconds OFF
7
5-time flash
2.5 seconds OFF
8
8-time flash
9
2.5 seconds OFF
1-time flash
Outdoor unit
2.5 seconds OFF
10
operates (at
low
frequency)
3-time flash
2.5 seconds OFF
11
4-time flash
2.5 seconds OFF
12
5-time flash
Outdoor unit
operates 2.5 seconds OFF
13
7-time flash
2.5 seconds OFF
14
8-time flash
2.5 seconds OFF
15
9-time flash
2.5 seconds OFF
16
The flashing frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the flashing frequency is "2".
ON
OFF
Abnormal point/ Condition
When compressor has stopped by overcurrent protection within
Outdoor power
1 minute 3 times in a row after compressor start-up, unit stops.
system
Outdoor When discharge temperature thermistor, fin temperature
thermistor or defrost thermistor shorts or opens during
thermistors
compressor running, compressor stops and restarts 3 minutes
later.
Outdoor control When nonvolatile memory data cannot be read properly,
system compressor stops and restarts 3 minutes later.
When the bus-bar voltage of inverter cannot be detected
Bus-bar voltage
normally.
Overcurrent When 12A(MUZ-A09YV, MUZ-A09YVH)/ 20A(MUZ-A12YV,
protection MUZ-A12YVH) current flows into power transistor module,
compressor stops and restarts 3 minutes later.
Discharge
When discharge temperature thermistor exceeds 116:,
temperature
compressor stops. Compressor can restart if discharge
overheat temperature thermistor reads 100: or less 3 minutes later.
protection
Fin temperature
When temperature at heat sink exceeds 83: or temperature of
thermistor overheat
inverter P.C. board exceeds 79:, compressor stops and
protection
restarts 3 minutes later.
When indoor coil thermistor exceeds 70:.
High pressure
When the defrost thermistor exceeds 70: in COOL mode.
protection
Compressor
When the waveform of compressor current is distorted.
sinusoidal current
Frequency drop by When current from power outlet exceeds 7A(MUZ-A09YV,
current protection
MUZ-A09YVH)/ 9A(MUZ-A12YV, MUZ-A12YVH), compressor
frequency lowers.
Frequency drop by
When indoor coil thermistor exceeds 55: in HEAT mode,
high pressure
compressor frequency lowers.
protection
Frequency drop by When indoor coil thermistor reads 6: or less in COOL mode,
defrosting in COOL compressor frequency lowers.
mode
Frequency drop by When discharge temperature thermistor exceeds 110:,
discharge compressor frequency lowers.
temperature
protection
When ambient temperature thermistor shorts or opens during
Outdoor
compressor running.
thermistors
Low discharge
When discharge temperature has been 40: or less for 20
temperature
minutes.
protection
When the overcurrent flows into IGBT(Insulated Gate Bipolar
PAM protection
transistor : TR821) or when the bus-bar voltage reaches 300V
or more, PAM stops and restarts.
PAM:
Pulse
Amplitude
Modulation
When the connector of compressor is disconnected, inverter
Inverter check
check mode starts.
mode
2.5-second OFF
www.ilmalämpöpumput.com
Detection method
0.5-second ON
2.5-second OFF
24
<Inverter P.C. board>
LED
Flashing
Checkpoint
· Check stop valve.
· Reconnect connectors.
· Refer to A "How to check inverter/
compressor" on page 26.
· Refer to G "Check of outdoor
thermistors" on page 28.
Replace inverter P.C. board after
check of A "How to check inverter/
compressor" on page 26 and G
"Check of outdoor thermistors" on
page 28.
Refer to A "How to check inverter/
compressor" on page 26.
· Check stop valve.
· Reconnect connectors.
· Refer to A "How to check inverter/
compressor" on page 26.
· Check refrigerant circuit and
refrigerant amount.
· Refer to G "Check of outdoor
thermistors" on page 28.
· Refer to L "Check of LEV" on page
30.
· Check around outdoor unit.
· Check outdoor unit air passage.
· Refer to I "Check of outdoor fan
motor" on page 29.
· Check refrigerant circuit and
refrigerant amount.
· Check stop valve.
· Check stop valve.
· Reconnect connector.
· Refer to A "How to check inverter/
compressor" on page 26.
The unit is normal, but check the
following.
· Check if indoor filters are clogged.
· Check if refrigerant is short.
· Check if indoor/outdoor unit air
circulation is short cycled.
· Refer to G "Check of outdoor
thermistors" on page 28.
· Refer to L "Check of LEV" on
page 30.
· Check refrigerant circuit and
refrigerant amount.
This is not malfunction.
PAM protection will be activated in
the following cases;
1Instantaneous power voltage drop
(Short time power failure)
2When the power supply voltage is
high.
Check if the connector is correctly
connected.
Refer to A "How to check inverter/
compressor" on page 26.
0.5-second ON