Mitsubishi Electric Mr. SLIM MSZ-FA25VA Technical Manual página 283

Check of compressor start failure
F
Confirm that 1~5 is normal.
•Electrical circuit check
1 Contact of the compressor connector (including CN61)
2 Output voltage of inverter P.C.board and balance of them (See 11-5.B )
3 Direct current voltage between DB61(+) and (-) on inverter P.C.board
4 Voltage between outdoor terminal block S1-S2
Does the compressor run for 10 seconds
or more after it starts?
After the compressor is heated with a drier,
does the compressor start? 1
Compressor start failure. Activate pre-heat control.
(Refer to 10-2. "PRE-HEAT CONTROL SETTING")
When OPERATION INDICATOR lamp flashes 6-time.
The thermistors in the outdoor unit are abnormal.
Check of outdoor thermistors
G
Defrost thermistor RT61
Measure the
resistance
between CN641
1 and 2 .
Discharge
temperature
thermistor RT62
Measure the
resistance
between CN641
3 and 4 .
Fin temperature
thermistor RT64
Measure the
resistance
between CN642
1 and 2 .
Yes
No
No
Yes
Disconnect the connectors CN641 and CN642 from the inverter P.C. board.
(Check the characteristics of each thermistor.)
Is the resistance of
Yes
thermistor normal?
(Refer to 11-6.1.)
No
Replace the
thermistor
except RT64.
In case that
RT64 is
abnormal,
replace the
inverter P.C.
board, since
RT64 is
combined with
the inverter P.C.
board.
Check the refrigerant circuit.
Check the stop valve.
Replace the compressor
Reconnect the
connectors
CN641 and
CN642.
Turn ON the
Does the unit operate
power supply and
10 minutes or more?
press
EMERGENCY
OPERATION
switch.
Resolución de averías
1
Heat with a drier for about
20 minutes.
Do not recover refrigerant
gas while heating
compressor with a drier.
Heating part
Replace the inverter
P.C. board.
No
Yes
OK.
(Cause is poor
contact.)
283